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ACG Series: Citations: Unit 3

In this Academic Communication Guide, learn about the basics of citations and some common citation styles and tools.

Unit 3: Citations - How to apply in-text citations to quotations and paraphrases

Unit Objectives:

At the end of this ten-minute unit, you will be able to:

a) understand the different ways of formatting in-text citations depending on how you convey your ideas, 

b) identify the differences between in-text citations with single or multiple authors, and 

c) learn that footnotes and reference lists vary in format depending on the citation system used.  

Unit 3 Contents


In-text Citations

1. Author-Date system

2. Numbered citations systems

In-text citations for long quotations 

  • APA
  • IEEE

Citing with multiple authors

Citing work discussed in a secondary source  

A final note on footnotes and reference lists 

Unit Summary


This unit provides examples of both APA and IEEE style conventions because these are the conventions most commonly used by NTU students. If your discipline requires a different style guide, such as MLA or Chicago, please look up those conventions separately. 

In-text Citations

When you refer to other people’s work to support your claims, you need to indicate the source immediately in the text. As outlined in Unit 1, there are two main conventions for in-text citations: author-date systems and numbered citation systems. 

1. In the Author-Date system used in the APA, the author’s surname and the year of publication are stated. Let us look at several examples to give you a clearer picture.  

Examples of in-text citations using the Author-Date system 


Information prominent citations 

Writing an academic essay is a challenge for first-time writers (Chaudhury, 2017).  

Writing an academic essay is ‘challenging for first-time writers’ (Chaudhury, 2017, p. 199).  


Author prominent citations 

Chaudhury (2017) suggests that writing an academic essay is a challenge for first time writers.  

Chaudhury (2017) suggests that writing an academic essay is ‘challenging for first-time writers’ (p. 199).  


All the examples above are correct. The first is an example of an information prominent citation while the second exemplifies author prominent citation. The main reason for picking one over the other is often a strategic one in which the writer decides to place the emphasis on the author(s) or topic(s) to enhance the narrative flow (Austin, n.d.). 

Information prominent citations prioritise information and are often used to introduce a research area in review and may include citations to several sources. citations prioritise information and are often used to introduce a research area in review and may include citations to several sources. They are also used to maintain writing flow and promote clarity. 

In contrast, author prominent citations are primarily used to build credibility by highlighting the fact that we are citing a known expert on the subject. We emphasise this by making the cited source the subject of the sentence.  

2. In numbered citations systems (e.g., IEEE) a number is inserted beside the cited text in square brackets or in superscript. This number also appears in the relevant entry in the reference list at the end of your work. References are always numbered in order of citation. The first reference you cite is always [1], the second always [2], and so forth. Similar to the author-date system, when you include quotations from a specific page, the page number is also inserted into the bracket.  


Examples of in-text citations using a numbered citations system  

The city of Singapore is populated by otters adapting to city life [1], and thus… 

As established in [1], the city of Singapore is populated by otters adapting to city life, and thus…  

XML is a new language developed from SGML and is expected to eventually replace HTML as the ‘language’ of web browsers [1, p. 7].   

In-text citations for long quotations

According to the American Psychological Association (2020), a long quotation is one that is 40 words or longer. Place the quotation in a free-standing block and omit quotation marks. Begin the quotation on a new line, indented ½ inch from the left margin (i.e., in the same place you would begin a new paragraph). Do note that for long quotations the page number is inserted after the full stop as seen in the following example. 


Example of a long quotation using APA style  

Lamont (2014) argues that the writer owns a voice to tell the reality of her experience:  

If there is one door in the castle you have been told not to go through, you must. Otherwise, you’ll  

just be rearranging furniture in rooms you’ve already been in. Most human beings are dedicated to  

keeping that one door shut. But the writer’s job is to see what’s behind it, to see the bleak  

unspeakable stuff, and to turn the unspeakable into words – not just any words, but if we can, into 

rhythm and blues. You can’t do this without discovering your own true voice (p. 192).  


In the IEEE system, a long quotation is one that has three or more lines. Use a block quotation by setting the block of quoted text as a paragraph and using a smaller font size for the block quotation. Lastly, indent the block from both margins. As this is a direct quotation, you must provide the page number(s) along with the in-text citation. One difference you should note is that for the IEEE citation system, the citation is placed within the sentence (i.e., before the full stop).  


Example of a long quotation using IEEE style  

As Abad notes:  

It is also desirable to minimise the parasitic capacitance of electronic packages because it is 

another source of signal delay. Consequently, a very low relative dielectric constant insulating 

material should be used whenever possible, since the relative dielectric constant is a measure of a  

material’s total polarizability and determines its charges storage capacity with respect to a vacuum 

[7, p. 63].  

Citing with multiple authors

Often, sources will have two or more authors. There are specific rules in APA style for how to format an in-text citation with multiple authors.  


For a source with two authors, name both authors in the signal phrase or in parentheses each time you cite the work. Use the word ‘and’ between the authors’ last names within the text and the ampersand symbol (&) in parentheses.  

Examples of citing a source with two authors in APA style 

Walia and Singh (2021) found that…  

Research has shown that…. (Walia & Singh, 2021). 


For a source with three or more authors, list only the first author’s name followed by ‘et al.’ in every citation, including the first, unless doing so would cause ambiguity between different sources.  

Examples of citing a source with three authors in APA style  

Jawad et al. (2021) argue that…  

Bilingualism is defined as…. (Jawad et al., 2021) 


You may have guessed that IEEE in-text citations do not make a distinction between sources with one author or more than one because only the reference number is indicated within the text.  

Citing work discussed in a secondary source

The American Psychological Association (2019) defines a primary source as one that ‘reports original work’ whereas a secondary source refers to ‘content first reported in another source’. While you are strongly encouraged to always cite primary sources, this may not always be possible. Among others, there are a few reasons why writers cite secondary sources. One reason could be that the primary source is no longer available as an out-of-print piece of work may be impossible to locate and it has not been digitalised. Another reason for citing a secondary source is that the primary source is in a language that you do not understand. Additionally, sometimes a secondary source that offers an easier to understand explanation in layman terms or additional critique or analysis may be preferable to cite. 


Example of citing a secondary source in APA  

In Alberts, Dawson and Michaels study (as cited in Downing & Muller, 1994)…  


IEEE style, however, does not allow for the use of secondary sources. The University of Murdoch (2021) recommends locating the original source of information and if it cannot be retrieved, it should not be cited.  

A final note on footnotes and reference lists

In Unit 1, we noted that a footnote or reference list requires detailed information about the author, the year of publication, the title of the source, the publisher, place of publication and the link to the source (if it is an online publication). The format of your footnotes and reference list varies not only between different citation systems but also between different types of sources, journal articles and edited books (among others).  

You could use a citation software and/or online resources to check that you are using the correct format for different types of sources. However, do not solely rely on the software because certain key information may not always be embedded in the file.  

You can find further resources on the topics of this unit at the following links from the NTU library:   

APA citation style  

IEEE citation style  


Quick Check  

  1. If you wish to cite a source to establish credibility, should you use the author-prominent or information-prominent in-text citation format? 

  2. Which of the following examples of in-text citations is correct, based on APA style rules?  

a. In their study, Fazilatfar et al. (2018) argue that EFL writers may commit unintentional plagiarism when writing courses, and instructors do not explicitly deal with ‘citation rules, strategies and academic literacy’ comprehensively (p. 9).  

b. In their study, Fazilatfar, Elhambakhsh & Allami (2018) argue that EFL writers may commit unintentional plagiarism when writing courses, and instructors do not explicitly deal with ‘citation rules, strategies and academic literacy’ comprehensively.  


Answers can be found on the 'Answers' tab.

Unit Summary

Congratulations! You have completed the Citations module. In this course, you learnt some of the ways of formatting in-text citations, which differ depending on how you convey your ideas, be it information or author prominent, and whether you are quoting or paraphrasing. You have also observed how the number of authors can change the format of an in-text citation and that at times it is acceptable to use secondary sources (depending on the citation system you are utilising). Lastly, you have learnt that footnotes and references vary in format.