Why this guide to punctuation?
The aim of this guide is to explain the aspects of punctuation that seem to cause most difficulties to students in their written academic work. Punctuation is used to organise or divide written text in order to make meaning clear. At the very least, poor punctuation detracts from the overall presentation of your writing and may give the impression that you have failed to edit and 'polish' your work. More serious problems can actually affect meaning and the way your reader understands what you have written. Good punctuation means following certain conventions, but it can also be a powerful tool in 'packaging' your text and in controlling the way your text is read and understood. In a written argument, punctuation can be used to enhance the point you are making.
This guide is not intended to be the definitive word on English punctuation in general. Rather, it concentrates on the difficulties frequently experienced by university students trying to write academic essays, reports, book reviews or theses. Other types of written texts that you may read, such as newspaper articles, letters, novels or legislation may use punctuation somewhat differently. We do not comment on these different ways of using punctuation because these guidelines are not directed at these different writing styles. This guide should make you better aware of how punctuation can be used to enhance your academic writing style, help you to write what you really mean and help you to proofread your work.
We have minimised the use of terms from 'traditional grammar' in our explanations and most of the examples we use are from real students' writing. Because we believe punctuation is so often related to meaning, particular 'tools' of punctuation (eg commas) are introduced in this guide according to what they are actually 'doing' and why.
Sentences are separated by a full-stop (.). It is commonly said that a sentence should contain a 'main idea', but may also contain optional 'extra' information. The notion of a 'main idea' is somewhat vague. So, sometimes you may find it difficult to decide whether to divide what you are writing into separate sentences, or whether to use punctuation and combine everything into one sentence. It might help to think of a sentence as somehow 'independent' and 'new'. In granting the status of separate sentence, you highlight this 'independence' or 'newness', and so increase the significance of what is written in each individual sentence. Conversely, by packing everything into one sentence you are subordinating some of the information and, therefore, conveying the message that some of the content is in some way 'extra' or supporting information. Overusing either strategy can make your writing difficult to follow.
Sentences with too little information
Consider this opening to a first year Political Science essay:
1. Sir John Kerr was forced to make a most courageous decision. The decision by Sir John Kerr was made even though he knew it would be unpopular. The Governor General made this decision for the benefit of Australia.
This writer begins his essay with a series of short sentences. He makes three points, and by giving each the status of a separate sentence, he presents each as an independent main idea. This increases the significance of each point, and slows the pace of the reader. However, this stop-start style appears not to be warranted because there do not seem to be three sufficiently independent main ideas. One sign of this is the repetition of 'Sir John Kerr' (twice) and 'the Governor General', although these refer to the same person, and the repetition of 'decision' (three times). On a closer look, the second sentence just elaborates on the first (ie why the decision was 'courageous') and so could have been combined with it. The third sentence also concerns the 'decision'.
This style is not necessarily bad, although it would make reading difficult if it continued throughout the essay. It should be reserved for when the writer particularly wants to increase impact in this way. The same ideas could have been expressed as follows:
2. For the benefit of Australia, Sir John Kerr, the Governor General, was forced to make a most courageous decision, even though he knew it would be unpopular.
Often students write sentences which do not have enough information to convey an independent main idea, and so are incomplete. Consider these examples:
3. The Governor General's statement to Whitlam "We shall both have to live with this".
4. A difficult time for the early colony.
5. When he was sent to Paris.
6. Being strongly in favour of reform.
In each case, the 'sentence' lacks an independent main idea. The reader must go outside the sentence to complete the picture. In 3) and 4) for example, what exactly about the 'Governor General's statement' or 'a difficult time' concerns us? Examples 5) and 6) are typical of a very common punctuation problem. They give independent sentence status to something which is really only extra information. This extra information should be attached to an independent main idea, as in the following:
7. When he was sent to Paris, Courbet pursued painting.
8. Being strongly in favour of reform, Keating argued for a republic.
Here the main ideas are that 'Courbet pursued painting' and that 'Keating argued for a republic'.
Sentences with too much information
Another common problem is to place too much within a sentence. This can make excessive demands on the reader and the writing may be difficult to understand.
There is more than one main idea
9. There are many reasons why the 1974 proposal for simultaneous elections was strongly opposed, Smith (1984), with whom I agree, argues that such opposition was well justified.
10. The economic environment is changing, the number of women re-entering the workforce has increased.
In these cases, the main focus of the sentence is less clear because there appears to be more than one possibility. The sentences do not have an obvious 'hierarchy', where one part of the sentence is the main idea, and the rest is extra information adding to it. In 10) for example, is the main idea about the 'economic environment changing', or 'the number of women re-entering the workforce', or some combination of these two? Sentences can contain two ideas that have equal significance, but that needs to be made explicit through a linking word such as 'and', 'but' or 'or':
11. The 1974 proposal for simultaneous election was strongly opposed, but that did not stop calls for the reform of the Upper House.
The sentence is too complicated
Sometimes it may be difficult to piece together the main idea of a sentence because the sentence is too complicated. This can happen when a lot of less important information is included which misdirects the reader's attention away from the main idea:
12. A combination of factors led to the realisation that a national authority was in the best interest, an example of these were factors such as defence, tariffs and free trade between the states, this combined with the idea that the founding fathers "sought to create a structure and process of government which reflected their dominant interests" has led the Constitution to be unsuitable for Australia today.
In this example, the main idea (we think!) is that "the realisation...combined with the idea...has led to...". As indicated by the dots, the main parts of the sentence are separated by lots of extra information. The writer's ideas could have been written as follows:
13. A combination of factors led to the realisation that a national authority was desirable. An example of these were such factors as defence, tariffs and free trade between the states. This combination, together with the idea that the founding fathers "sought to create a structure and process of government which reflected their dominant interests", has led the Constitution to be unsuitable for Australia today.
The chain of argument is too long
You may find sentences where there is nothing actually incorrect in terms of the rules of grammar, it is just that the chain of argument is too long. The sentence is more difficult to follow than it needs to be:
14. So, if constitutional reform is going to be possible, to the extent of updating its principles to today's standards, the amendment of section 128 will be needed to decrease the number of states needed to pass a referendum from four to three, in this way effectively making all other revisions to the Constitution less of a problem than has been previously experienced.
Dividing example 14) into two sentences would have allowed the writer to focus the reader's attention on some aspect of what she was communicating and would have given the reader a break. For example, the first sentence makes a statement that if X is to happen ('constitutional reform'), Y will be necessary ('the amendment of section 128'), and this will lead to Z (the consequence - 'make all other revisions...less of a problem'). Putting a full stop after 'three' would separate the two 'actions' from their consequence, and so better focus the reader's attention on both:
15. So, if constitutional reform to the extent of updating its principles to today's standards is going to be possible, the amendment of section 128 will be needed to decrease the number of states needed to pass a referendum from four to three. In this way, all other revisions to the Constitution would be less of a problem than has been previously experienced.
Different types of sentences
It is possible to end a sentence with forms of punctuation other than the full-stop, and so create different types of sentence.
A question mark is used when the sentence is actually asking a question. In academic writing, questions are usually used to help set up an argument and signal the structure of the text to the reader. A question may be particularly useful at a key point in an argument:
16. How, in such an environment, do plants receive the nutrients they need?
17. How has inequality sustained itself?
In such cases, the writers are committing themselves to somehow answering the questions, or at least discussing the issues, etc that they raise. An academic reader will expect the writer to do this. Note that a question mark is not used when only referring to or discussing a question, as in these re-wordings of the examples above:
18. Researchers investigated how, in such an environment, plants receive the nutrients they need.
19. It is not known how inequality has sustained itself.
In these cases, the writer is not actually asking a question, but commenting on what 'researchers investigated', and about what 'is not known'.
Sometimes, at the end of an academic text, questions are used to draw the reader's attention to the implications or significance of the argument presented. In these cases, a reader would not expect a writer to respond to the questions, but understands that such questions are used to take the reader beyond the immediate text and into the concerns of the wider academic discipline. In the academic world, responding to a question or problem frequently raises further questions or problems.
Exclamation marks are used to show that something is being stated vehemently. An exclamation mark is one way of adding emphasis. Sometimes students use exclamation marks to highlight something they have written, to try to make the significance of their point more obvious. You may be especially tempted to do this when you feel strongly about something, as in the following example:
20. Streaming leaves no student under an illusion; students (and their parents!) are clearly aware of their perceived ability.
However, the exclamation mark is rarely used in academic writing. Most academic staff feel that if something is significant, then they as readers should be able to identify this for themselves. The style of writing itself should make the significance clear. The student's example above could have been re-worded in one of the following ways:
21. Streaming leaves no student under an illusion; students are clearly aware of their perceived ability, and so too are their parents.
22. Streaming leaves no student under an illusion; not only students, but also their parents are aware of students' perceived ability.
23. Streaming leaves no student under an illusion; students are clearly aware of their perceived ability. Parents are aware of it too.
Within the sentence
There are various tools of punctuation which divide the sentence itself into parts. By interrupting the flow of reading, they draw the reader's attention to the different parts of the sentence and how they work together to convey its main idea.
When to use the comma
The comma is the most frequently used form of punctuation and signals a break in the flow of the sentence. Perhaps because the reasons for breaking the sentence flow may be quite complex, there is a range of views on when it is appropriate to use the comma. You may find that this contributes further to your uncertainty. However, it is relatively safe to say that in academic writing, commas can be used to:
- separate extra information from the main idea of the sentence
- separate linking words from the main idea of the sentence
- separate conditions from a possible outcome
- list things, concepts, events, ideas, etc
- resolve ambiguity.
Separating extra information from the main idea of the sentence
Extra information may take many forms. It may entail details about place, time, manner, nature or reason, or provide an example, or a linker to other parts of the text. If there are no commas, it is left to the reader to distinguish between the main idea and anything extra, and this increases the burden of reading. Consider the following examples in which commas were not used:
24. In Australia surgeons must use approved procedures.
25. In order to achieve a practical system of internal control a degree of trade-off between costs and benefits is required.
26. Schooling together with family values reproduces class inequality in society by preparing students for social positions which on the whole correspond to their social heritage.
27. Long term creditors require information about the solvency of the business that is its ability to pay interest and repay the loan.
See whether the insertion of commas helps you to understand the examples more easily:
28. In Australia, surgeons must use approved procedures.
29. In order to achieve a practical system of internal control, a degree of trade-off between costs and benefits is required.
30. Schooling, together with family values, reproduces class inequality in society by preparing students for social positions which, on the whole, correspond to their social heritage.
31. Long term creditors require information about the solvency of the business, that is, its ability to pay interest and repay the loan.
The notion of 'extra' ie 'not absolutely necessary', is very important in your decision about whether or not to insert a comma. If the information in some way defines the concept that you are writing about, you do not use a comma. Consider the following:
32. The families, who live in the more affluent areas of Sydney, received the most benefit from school de-zoning.
This sentence has a somewhat different meaning from the following one:
33. The families who live in the more affluent areas of Sydney received the most benefit from school de-zoning.
The first sentence implies that the reader has already read something about 'the families' and is now being offered two further pieces of information. The important one is that these families 'received the most benefit from school de-zoning'. The extra information is that they happen to 'live in the more affluent areas of Sydney'. In the second sentence, the fact that these families 'live in the more affluent areas of Sydney' defines the families that 'received the most benefit...'. This fact is not extra information but part of the main idea.
Separating linking words from the main idea of the sentence
Commas are used to separate linking words from the main idea of the sentence. The linking word indicates the relationship between one sentence and another, or between different parts of the one sentence. By using a comma, a writer draws the reader's attention to the nature of the relationship indicated by the linking word. For example, words like 'and', 'also', 'furthermore', 'moreover' indicate that something is being added, while 'but', 'however' and 'yet' indicate a relationship of contrast. Other relationships include similarity ('similarly', 'again'), conclusion ('therefore', 'so', 'as a consequence', 'consequently', 'as a result'), and alternative ('or', 'on the other hand'). Consider the following examples:
34. Finally, it is difficult to accurately predict whether reform will succeed.
35. This form of reporting prejudices the small organisations by leaning in favour of the larger ones, and discriminates against the important issues by focussing on the sensational ones.
The use of the comma relates to the length of the linker. As a general rule, if the linker is a long word (eg 'however' or 'consequently') or has more than one word (eg 'on the other hand' or 'as a result of this'), a comma is usually used. See how its omission affects the following sentence:
36. Yet on the other hand if the proposed amendments to the Constitution were marketed in a new way then the possibility of success would have to increase.
With short linkers, omitting the comma makes the linking word less conspicuous, and so the relationship between different parts of the sentence may be less obvious. The choice of whether or not to insert a comma depends on what you want to achieve. So, there is a difference in emphasis in the two following sentences:
37. 3Again, the affluent families benefited.
38. Again the affluent families benefited.
Separating conditions from a possible outcome
In English there are language structures which refer to situations where something may happen or 'exist' if something else happens or 'exists'. In such sentences, a comma is used to separate the two parts of the sentence:
39. If Parliament is truly for the people, then we have a right to know what is going on.
40. If average rainfall continues to decrease, irrigation will be necessary.
Listing things, concepts, events, ideas etc.
Perhaps the simplest function of the comma is to separate items of information that form a list, and then those items from the other parts of the sentence. Commas are usually used when the items in the list are relatively uncomplicated. Semi-colons are often used when the items are longer or more complicated (see section on 'semi-colons').
41. The Revolution was prompted by the bankruptcy of the kingdom, heavy taxation on the lower classes, the large population and the disparity between the living conditions of the classes.
42. Many native animals have symbolic significance, including the emu, the kangaroo, the wombat, the echidna and the platypus.
Sometimes a comma is necessary because the sentence would be ambiguous and confusing without it. Consider the following pair of sentences:
43. Sir John Fraser, said the Kaiser, had a contemptible little army.
44. Sir John Fraser said the Kaiser had a contemptible little army.
When not to use the comma
In an enthusiasm to use punctuation, you may use commas where they are really not necessary. Perhaps you may think that, when in doubt, it is better to err on the side of using too many commas than too few. However over-using the comma can interrupt the flow of reading, or even cause confusion.
In the section on 'extra' information we have already dealt with situations where the information defines a concept and, therefore, is not divided off by a comma. Look again at the following sentence and see how the unnecessary comma misleads the reader:
45. The inaccurate reporting, of the lymphatic imbalances, delayed treatment for a further six months.
In example 45), the reader could legitimately assume that the fact that the reporting concerned 'lymphatic imbalances' was marginal, when really it is part of the main idea. Similarly, in the following examples, the use of the comma may confuse the reader because the interruptions do not reflect logical breaks:
46. The cultural baggage a child receives, is the starting point for schooling.
In example 46), the main idea is that "X is the starting point for schooling", where X is 'the cultural baggage a child receives'. A comma is not necessary.
47. Perhaps the poet used the word 'lilting', for its alliterative qualities.
In example 47), the main idea of the sentence is to suggest why the poet used the word, and so the reason 'for its alliterative qualities' is not extra information. It is the reason for the poet's use of the word 'lilting' that is in question, not whether or not the poet used it.
48. A Liberal backbencher agrees that, "there's not enough exposure to the issues...".
In example 48), the quote is meant to be read as a part of the writer's sentence, and so it should flow directly from the writer's words.
49. Some say, that the circumstances of a child's birth greatly influence the status of a child.
In example 49), the comma after 'say' is unnecessary because what some people say is the main idea of the sentence. A comma would be necessary had the sentence been "According to some, the circumstances...", because in this case the information about who says it would be presented as extra information to the main idea.
50. The other major short term stimulus introduced in the One Nation package is the reduction of the wholesale sales tax on luxury, passenger motor vehicles from 20 per cent to 15 per cent.
In example 50), 'luxury' is part of the description of the type of motor vehicle. A comma placed after 'luxury' would make the reader think that 'luxury' is the first of a list of things on which the tax has been reduced.
51. The first study was written by Kenley and Staubus and was published, in 1972.
In example 51), the comma should go after 'Staubus', because it is the 'and' that introduces the extra information about the time of publishing. If there is no comma after Staubus, the second 'and' suggests the next word might be another author's name. But there should be no comma before 'in' because 'published' and 'in 1972' need to be taken together.
When to use the semi-colon
In students' writing, the most common use of the semi-colon is to separate items in a list where the items are themselves long and/or complicated, or the writer wants to highlight them by making them more conspicuous than could be achieved with commas. For example, in a list of persons, places or dates one would use commas, but when the items in the list are reasons, consequences, conditions, examples, findings and so on, then semi-colons may be appropriate. Note these examples:
52. Therefore, it can be said that the main arguments for retaining our present Constitution in its original context are: firstly, its survival and its bringing us successfully through numerous controversial events; secondly, the flexibility of the language.
53. Stimulating the economy is something the government plans to do in the short-term and the medium-term: in the short-term,...; and in the medium-term,...
Sometimes, a semi-colon is used instead of a linking word. This use of the semi-colon suggests a strong relationship between the two statements but leaves it up to the reader to decide what the relationship is. Because this is not explicit, you would not want to use this form too often.
54. The sharecroppers were poor and exploited; the Joabs were violent.
When to use the colon
In academic writing, colons are often used when the writer introduces material (a quotation, data, a figure or diagram etc.) that explains, enlarges or summarises the comment that precedes it. This often occurs with material that is borrowed from another text. The colon indicates that the material will immediately follow:
55. Kelly (1989:107) has a different view:Both men knew each other well and each knew where the other stood, and each thought he had the other's measure. The Prime Minister thought Kerr would not dare use the reserve powers, and if he tried, then Whitlam would get in touch with the Palace first and have Kerr's commission revoked.
56. Kangaroo numbers declined significantly during the early 1980s: 5432, 1981; 4968, 1982; 4549, 1983.
The colon may also be used to introduce a list which is long and/or complicated (see sentences 52) and 53)), or which the writer wishes to make more conspicuous:
57. Education policy in the sixties continued to be constrained by two perennial issues: sectarianism and geography.
When to use brackets (parentheses)
Brackets (sometimes called parentheses) share one of the functions of the comma, in that they are used to indicate information that is somehow extra to the main idea of the sentence. Brackets enclose words which are marginal to the main idea, and so have the least force in interrupting the flow of the sentence. For many students, perhaps the most common use of brackets is for referencing (using the Harvard system). In this case, the year of publication, or both the name of the author and the year of publication, are placed between brackets, as in the following examples:
58. Brown (1992) shows that deserts are increasing.
59. Recent research (Brown 1992) shows that deserts are increasing.
Other reasons for using brackets might be to provide an example, to qualify a point, to refer the reader to another part of your text, or to give additional detail where this might be useful to the reader. Consider the following examples:
60. Serious weather disturbances (eg electrical storms) are increasingly common.
61. Most western industrialised nations (America is an exception) have changed rapidly.
62. The kangaroo population has also been affected (see below).
When you use brackets, make sure you check the following: firstly, that you have not put within brackets any information that should be more prominent; and secondly, that the sentence makes sense without relying on the bracketed words. Be especially cautious when there is a lot of writing between the brackets.
When to use the dash
In informal writing, dashes are sometimes used to separate parts of a sentence. In academic writing, they suggest a hastiness which is not appropriate in a well considered argument:
63. Peter Howson – a Liberal Minister at the time – recorded this in his diary.
64. The play deals with a very pertinent issue – the way in which society imposes restrictions upon individuality which transgresses social norms.
Examples 63) and 64) would have been better written as:
65. Peter Howson, a Liberal Minister at the time, recorded this in his diary.
66. The play deals with the very pertinent issue of the way society imposes restrictions upon individuality which transgresses social norms.
Within the word
The hyphen looks like a dash, but it is used to connect the parts of compound words, as in economic decision-making or day-to-day activities. It is particularly used in newly formed compound words, like 'boot-up your computer', or where combining a prefix and a word could lead to mispronunciation, as in co-opt or pre-eminent. In well-established compound words the hyphen may sometimes be omitted, so that hare-lip and harelip are both acceptable.
If you know a European language, in which words can be split with a hyphen at the end of a line of text, you may be tempted to do the same in English. This pattern is not widely used in current academic English, and the only words which are regularly divided at the end of the line are long compound words, which should be split after the hyphen. So, if you know that you will not be able to fit a word at the end of a line, write the whole word on the next line.
One common use of the apostrophe is to show that two words have been contracted into one and some letters have been omitted (eg can't, haven't, they've). Many academic staff still consider these words inappropriate for formal academic writing, so exercise care when you use them. Expanded versions may be safer to use (eg cannot, have not, they have).
The apostrophe is also used to indicate 'possession' ie that something is possessed, or somehow connected to or associated with something or someone else. The apostrophe is used at the end of the word, and an s is added. When the word is a plural (ie more than one) and the last letter of the word is an s, then no extra s is needed:
67. Australia's balance of payments will continue to be a problem.
68. Many writers' difficulties can be caused by uncertainty. (Note: plural and the last letter is an s)
If the word is singular (ie one) but ends in an s, you may choose whether to add an extra s. Both of the following forms would be considered correct:
69. Goss' rise in Queensland politics was not expected.
70. Goss's rise in Queensland politics was not expected.
Sometimes students will incorrectly add an apostrophe where there is no possession intended, at least in the way the sentence is worded:
71. The conflict offered the nationalistic German's (Germans) the opportunity to prove their superiority.
However, the more frequent error students make is to omit the apostrophe when it should be used:
72. One of the greatest influences on a persons (person's) role development is that of schooling.
Because of these two uses of the apostrophe, many students confuse it's and its. The first form is simply a contracted form of 'it is' or 'it has'. The following sentences illustrates its correct usage:
73. It's only a matter of time before the Federal Constitution becomes a political issue. (It's = It is)
74. It's been only a few years since the last referendum. (It's = It has)
The second form, without the apostrophe, signals possession. It is the non-male/non-female version of his and her, and is an exception to the earlier use of the apostrophe.
75. In its wisdom, the Ethics Committee decided to revoke the recommendation.
Here is an example which contrasts the two forms:
76. It's unlikely that the economy will achieve its true potential.
As contractions are often considered too informal for academic writing, you may easily avoid the problem by writing 'it is' for the first form and reserving 'its' for the possessive form.
Making words stand out
Quotation marks (inverted commas)
Quotation marks may be either single (' ') or double (" "). The two forms are not used differently (note the examples below), but it is important to be consistent in using the same form throughout your writing.
Words quoted directly from another text
Quotation marks are most frequently used to show that words are being quoted exactly as they appear in the original text:
77. Witherford (1990:21) argues that "computers will transform the nature of teaching".
Quotation marks are not used if the words are not exactly the same as in the original, but instead have been paraphrased by the writer:
78. Computers will affect the nature of many professions and, according to Witherford (1990), teaching is no exception.
At rare times you may need quotation marks within a text that is already in quotation marks. In such cases, use both single and double quotation marks and be particularly careful to be consistent:
79. Brown said: 'The first words of Melville's Moby Dick, "Call me Ishmael", are full of significance'.
Words used in a special way
Another common use of quotation marks is to show that words are being used in a special way. There are a number of reasons why a writer might do this. One is to show that a word is being explicitly referred to, and so is not performing its usual function in the sentence. This is often done in academic disciplines where words are themselves under study, such as in Literature or Linguistics:
80. The poet's use of 'black' and 'shiver' suggests that the night is cold.
81. More and more writers use 'their' when no plural is meant.
Another reason is to show that a word represents a term, concept, or anything else that is being mentioned for the first time. This signals to the reader that the word has a meaning that may be particular to the academic discipline:
82. For modern feminists, 'work' includes more than just paid employment.
83. An Abaluya may have a number of "mothers" but only one "father".
A third reason is to show that the use of a word is not necessarily accepted by the writer, and that the word is open to challenge:
84. The 'disadvantage' is temporary and cannot be equated with the situation of the Indians.
85. Bruges's conception of "society" is too broad to be useful.
A fourth reason is that the word is foreign but the writer either does not have an exact English term, or particularly wants to use the original term:
86. They stayed at a 'ryokan' and visited the temple at dawn.
A fifth reason is to signal extracts (articles, short stories from a collection, poems from an anthology etc.).
87. Keats is historically inaccurate in his reference to Cortez, in 'On First Looking into Chapman's Homer'.
Non-traditional forms of punctuation
With the widespread use of computers, other ways of marking words are becoming increasingly common. Italics and underlining are often used as alternatives for quotation marks. Bolding and the use of contrasting fonts are more commonly used for sub-titles or for the emphasis of particular words or phrases in the body of the paragraph. This is particularly common in reports and longer essays.
When you do opt for some of these strategies, you need to be mindful of the total appearance of your text. For example, it is a common mistake to use too many different fonts or different font sizes, and so make the text distracting. Keep in mind that persuasion in academic writing depends on argument rather than just on attracting attention, as it sometimes does in advertising and journalism. So if you want to emphasise some point, it is almost always preferable to do it through your choice of words and the way you express yourself, rather than through exotic fonts or 'busy' layout.
Other sources of information
Australian Government Publishing Service (1994) Style Manual for Authors, Editors and Printers of Australian Government Publications, 5th edition, Canberra.
Bate, D. and Sharpe, P. (1990) Student Writer's Handbook, Harcourt Brace Jovanovich, Sydney.
Burt, A. M. (1983) A Guide to Better Punctuation, Stanley Thornes, Cheltenham, England.
Owen, J.W. and Davies, J. (1982) Solve your Punctuation Problems, Pitman, Victoria.
Quirk, R., Greenbaum S., Leech G., Svartvik J. (1972) A Grammar of Contemporary English, Longman, London.