An Introduction to Author–Date Referencing
At the tertiary level, each school or department has a stated preference for the referencing style students should use when completing assignments for courses. The two most commonly required referencing styles are APA and Harvard, both of which are author–date referencing styles. In this blog article, I will explain the basics of author–date referencing. All illustrative examples use APA Style. By the end of this article, you will understand:
- that there are many different author–date referencing styles
- the basic rules of any author–date referencing style
- that when referencing, consistency is always the most important consideration.
If your school requires you to use a footnote referencing style, please see our blog article 'An Introduction to Footnote Style Referencing'.
You can also watch our video on YouTube, in which Dr Lisa Lines discusses author–date referencing.
The Many Styles of Author–Date Referencing
Author–date referencing styles get their name from the use of both the author family name/s and date in parenthetical citations, for example, (Lines, 2017). A page number will also be included whenever the ideas or words of a source are being paraphrased, summarised or quoted (e.g. Lines, 2017, p. 1).
APA and Harvard are only two of the many author–date referencing styles that exist. Another well-known style of this type is Chicago (Author-Date)—also known as Turabian—and many publishers and journals have their own author–date referencing styles for authors to follow.
Moreover, there is no one rigidly defined Harvard style in the same way as for APA. Rather, it is collection of guidelines that, when used by institutions, publishers and journals, results in significant variation in what is considered ‘Harvard style’. This means that the Harvard style required by one university may differ markedly from that required by another.
Whichever style you are required to follow, you must locate the appropriate referencing style guide to follow, and adhere to it exactly, ensuring consistency throughout your referencing. This need for consistency is discussed further below.
The Basic Rules of Author–Date Referencing
Although they vary in a few ways (e.g. the use of punctuation, as explained below), all author–date referencing systems have much in common with one another. Note that while all of the examples below are in APA referencing style, these same basic rules are true for all author–date referencing styles.
When to Provide Page Numbers
When citing an entire work, the page number or range can be omitted. However, in all other cases, a page number (or location information in the case of unpaginated sources, such as websites) is necessary. In APA, this looks like this:
Citing an Entire Source
A common reference work is McCarthy and O’Dell’s (2005) English collocations in use.
Summarising an Idea from a Source
Knowledge of collocation is vital for the development of fluency in second language learners (McCarthy & O’Dell, 2005, pp. 10–11).
How to Cite Works by Multiple Authors
Sources with two authors use either ‘&’ or ‘and’. APA uses ‘&’.
Sources with three or more authors use et al., either in every instance or only for subsequent citations. In APA, for sources with three to five authors, et al. is used for subsequent citations only:
In-text Citation—First Mention
(Waring & Takaki, 2003; Zavera, Schwanenflugel & Nikolova, 2005)
In-text Citation—Subsequent Mentions
(Waring & Takaki, 2003; Zavera et al., 2005).
Waring, R. & Takaki, M. (2003). At what rate do learners learn and retain new vocabulary from reading a graded reader? Reading in a Foreign Language, 15, 1–27. Retrieved from http://nflrc.hawaii.edu/rfl
Zareva, A., Schwanenflugel, P. & Nikolova, Y. (2005). Relationship between lexical competence and language proficiency. Studies in Second Language Acquisition, 27, 567–595. https://doi.org/10.1017/s0272263105050254
In APA, for sources that have six or more authors, et al. is used in every instance.
How to Differentiate Works Published by the Same Author in the Same Year
When citing multiple sources by the same author published in the same year, these are differentiated by adding a letter to the end of the year of publication in both the citation and the reference list. In APA, this looks like this:
(Nation, 2015a, 2015b)
Nation, P. (2015a). Changing my mind about the role of the teacher in language teaching. Contact (TESL Ontario), 41(3), 36–37.
Nation, P. (2015b). Which words do you need? In J. R. Taylor (Ed.). Handbook of the word (pp. 568–581). Oxford, England: Oxford University Press.
When to Omit the Author or Year from the Parenthetical Citation
If you have referred to the author in the narrative of your text, you should not repeat the author name in the corresponding parenthetical citation. Likewise, if your sentence mentions the year of the source, there is no need to include the year in the parenthetical citation. In APA, you might see the following:
As Melka (1997, p. 90) explained …
In 2003, a study was published that … (Nesselhauf, p. 225).
Richards’ seminal 1976 study found … (p. 92).
The author or date is never omitted from the parenthetical citation simply because it isn’t known. If no year of publication is available for a source, use ‘n.d.’ instead (i.e. ‘no date’). If the author isn’t known, use the title of the source instead.
There Must Be a Reference List or Bibliography
The purpose of in-text citations in author–date referencing styles is to give enough information to point the reader to the full bibliographic entry at the end of the document. This can be a reference or works cited list (which contains only those sources cited in the body of the text), or a bibliography (which contains all the sources cited in the body of the text, as well as any important works consulted but not cited).
The considerable variation between author–date referencing styles, and between the versions of the same style of different institutions, publishers and journals, means that there is plenty of room for confusion for students when they are trying to follow a referencing style guide.
If you are a student writing at the undergraduate or postgraduate level, it may be comforting to know that, while you should make every effort to adhere to the referencing style guide you are following, your most important concern should be consistency.
Even if you use some variation on your chosen referencing style, so long as you do so consistently, and it does not contradict any of the basic rules of author–date referencing given above, you should not be penalised.
The same cannot be said for authors submitting manuscripts to journals or publishers. In this case, the referencing style guidelines of the journal or publisher must be followed exactly, without variation. Failure to do so can result in your manuscript being returned to you for correction.