Citation, or the practice of documenting the sources you use in your writing, is a core element of academic research and writing, regardless of discipline. Citing sources not only allows you to document the scholarly conversation into which you’re entering. This is part of producing knowledge; documenting what and who you’ve read in the course of writing your paper is a mark of effective scholarship that meets the expectations of academic integrity.

Citation Formatting

Proper citation includes two parts: in-text citations and a complete reference list of sources from which these arose. In-text citations show the reader the specific information you have used in your paper and where exactly you draw on these sources in your discussion. The list of sources at the end of your paper gives the exact references you used, which allows anyone to easily find and refer back to them.

In STEM disciplines, there are different ways to format and organize citations, and these “style guides” are discipline-specific (and sometimes course-specific) (Hochberg, 2019, p. 14). Be sure to check with your instructor about which style they would prefer before you write your first lab report or paper.

Discipline/Subject Association/Organization Style Guide
Chemistry American Chemical Society ACS Citation Style Guide
Mathematics American Mathematical Style AMS Style Guide
Psychology and many other social science disciplines American Psychological Association APA Citation Style Guide
Some Engineering disciplines American Society of Civil Engineers ASCE Citation Style Guide
Various STEM disciplines The University of Chicago Press Chicago Manual of Style
Biology and other various STEM disciplines Council of Science Editors CSE Citation Name-Year Style Guide
Various engineering disciplines including:

Civil Engineering, Biomedical Engineering, Electrical and Computer Engineering

Institute of Electrical and Electronics Engineers IEEE Editorial Style Manual
Medical and Scientific journals; various Engineering disciplines International Committee of Medical Journal Editors Vancouver Style
Physics American Institute of Physics AIP Citation Style

When deciding which style of citing to use, make sure you follow any directions you were given. Once you choose a style, you must stick to it throughout your whole article. It is very important to be consistent with your formatting; it makes it easier for the reader to follow!

Check out UBC’s Library Tutorial on Citing Sources for a series of helpful videos!

What and When to Cite

It can be difficult to know when and what to cite. You always need to cite:

  • Ideas, concepts, opinions of others
  • Direct quotes, summaries, and paraphrases
  • Facts used as evidence
  • Tables, graphs, or figures produced by anyone but yourself
  • Specific statistics or data

You may have heard that you don’t need to cite your source when the information you’re including is common knowledge. Generally, common knowledge can be understood as information that an average reader would accept without having to look up. This includes:

  • Information that most people know (such as that water freezes at 0 degrees Celsius),
  • Information shared by a cultural or national group (such as the names of Canadian prime ministers)
  • Knowledge shared by members of a field or discipline (such as that a double bond is stronger than a single bond)

However, it can be difficult to know what counts as common knowledge, because an “average reader” is audience and discipline specific. What might be common knowledge in one cultural group or academic discipline may not be common knowledge in another. Here are some ways to determine if something is common knowledge or not:

  • Ask: who is my audience and what can I assume they already know?
  • See if the information is cited or not in academic scholarship. If the information is cited in at least three different sources, it’s probably common knowledge
  • If you are not sure, assume the information is not common knowledge and cite. It’s always better to over-cite than under-cite.

Paraphrasing and Quoting

Paraphrasing means putting something that someone else has written into your own words, phrasing and sentence structure.

  • Because you’re presenting someone else’s ideas (even though you’re not saying it in exactly the same way), it’s important to acknowledge this with a citation.
  • Paraphrasing is useful because it shows that you have an understanding of the material and it allows you to keep your writing concise.

Quoting means reproducing the same words that someone else has written.

  • Not only does a quotation need an in-text citation with a page number, but it also needs to be presented in quotation marks.
  • Use quotations if a piece of information is well-phrased or unique and cannot be simply rephrased to have the same effect. For example, don’t write: Cliff et al. (1989) reported that “A total of 591 great white sharks Carcharodon carcharias were caught between 1974 and 1988 in the gill nets which are maintained along the Natal coast to protect bathers from shark attack” (p. 77).  Instead, write something like: Nearly 600 great white sharks were caught in gill nets along the Natal coast between 1974 and 1988 (Cliff et al., 1989, p. 77).

Reporting Expressions

One way of making sure that you’re signalling to your reader when you’re including someone else’s work is to use something called a “reporting expression.” Reporting expressions signal that you are summarizing or reporting what someone else has written. Examples of reporting expressions include words such as writes, argues, finds, demonstrates, suggests, claims, explains, or shows.

Reporting expressions also allow you as a writer to take a position. For example, writing “Reilly (2010) shows that more than one cup of coffee slows response rates in people” is different than writing “Reilly (2010) suggests that more than one cup of coffee slows response rates in people.” Here, “shows” implies that you agree with Reilly, whereas “suggests” implies that you might have some uncertainty about Reilly’s research. It’s important to choose your reporting expressions carefully!

A helpful hint with citing: if you’re using a reporting expression, you still need to include an in-text citation. This is because you’re reporting what someone else has written, and you need to be sure to credit them for their work.

Further reading:


Michael Hochberg, “Citing, Reading and Searching,” in An Editor’s Guide to Writing and Publishing Science (Oxford University Press, 2019), 14.

Further reading: