Citing Sources

What is a citation?

To cite something is to quote it, or to refer to it as an authority or as an example. Pointing to the source of that quote is a “citation”. There are different types of citations and citation styles depending on your area of study.

Here’s a definition of what a citation is in academic writing and a bit of explanation following:

“a written reference to a specific work or portion of a work (book, article, dissertation, report, musical composition, etc.) produced by a particular author, editor, composer, etc., clearly identifying the document in which the work is to be found” (Reitz, 2014) 

  • Source: that definition is from the Online Dictionary for Library and Information Science
  • (Author, Date): the name and date in parentheses just after the title are an ‘in-text citation’. That is where the author and publication date appear in the main body of a work. 
  • Full citation for bibliography: the entire listing for the resource–author, title, date, publisher and any other details–would appear in a document at the back of any paper or article in the list of ‘references’. It would look like this:

Why we cite

To give others credit for their work 

Imagine how you feel when someone else uses your ideas or words and doesn’t give you credit. Your ideas matter, therefore so do the ideas of others. Scholarship, and knowledge creation in general, is a process that develops over time and through the work of many scholars. Students are a part of the scholarly community. You’re expected to acknowledge how the ideas of other thinkers influence your own.

To point to the original work 

Whoever is reading your work may need to find the original sources that you’re building on or quoting. Many scholarly articles include a section called a ‘literature review’. This is where you summarize the writing and learning on your topic that’s been done by others. Your reader may use that section as an introduction to the topic. They’ll need to know what the major ideas are and where to find them. Your citations will help them locate the original writings.

To give strength to your ideas

You can support your ideas by showing that other scholars agree. But even when you disagree with an idea, you give credit to that person for their work. Disagreement, and the back-and-forth that comes from engaging in conversation about ideas, is part of the process of discovering and refining knowledge. Proper citation shows respect for the work of others just as you expect the same respect for your own work.

Using others’ ideas and not citing = plagiarism

Plagiarism is intellectual theft. By not giving credit to the thinkers you consulted for your work, you make it seem as though their ideas are yours. That is plagiarism. You may also have heard it called ‘copying’ or ‘cheating’.

This includes submitting as new the work that you’ve previously turned in or published. Self-plagiarism is a real thing.

Like someone else’s idea? Share it, don’t steal it. ; )

Plagiarism damages your reputation within the academic community. It can call into question your skills or motivations. It limits how well you can participate in the scholarly conversation. 

Plagiarism also has repercussions in the professional world. Consequences can include:

  • Losing your job
  • Losing your reputation or credibility (employers may not want to hire you)
  • Legal repercussions (someone can sue you for stealing their intellectual property)

Not sure you’re not accidentally plagiarizing? Practice by taking the Library’s Plagiarism Tutorial

Citation style guides

What’s a style guide?

A style guide describes the format that scholars use to cite their sources. Style guides vary by area of study (discipline or profession). These guides were originally created to help in the preparation of manuscripts that were being published as articles or books. While there are a number of style guides, the three main guides you’ll come across as a student are APA, Chicago, and MLA.

  • The Chicago Manual of Style
  • The Publication Manual of the American Psychological Association (APA), Seventh Edition
  • Modern Language Association Handbook (MLA), 8th edition

Professional organizations (chemists, historians, etc.) have developed the formatting rules for how new learning is published. This can be anything from the width of the margins in an article to the way that citations are presented within the text and/or in the reference list at the end of the manuscript.

Formatting rules exist to help make your paper easier to read and understand.

Students are scholars in training. For that reason, you’ll be expected to format your writing (depending on the assignment) according to the style guide that corresponds to your subject area. So an Introduction to Psychology class may use the Style Guide of the American Psychological Association (APA) while a History course on the African Diaspora may use the Chicago Manual of Style (Chicago).

Basic types of citations (check your style guide for specific instructions)

  • In-text or parenthetical citation: when you cite your source within the body of your text. Included is usually last name and publication date
  • Footnote: citation on the same page where the quoted text appears. You mark the quote with a small number (superscript).
  • Endnote: citation that appears at the end of a chapter or section of text. You mark the quote with a small number (superscript).
  • Reference list or Bibliography: the complete list of all your sources. This list goes at the end of your paper.
  • Annotated bibliography/reference list: a list with an explanatory note or comment for each reference item. This assignment might be part of the research project and can help to organize your work.  

Citation style resources 

SDSU Research Guides

Reference/Find Facts Research Guide

Looking for other research guides? Start here: Research by Subject

Selected links to content at style guide websites
APA: American Psychological Association

Reference Lists versus Bibliographies 


Instruction Aides – examples, handouts, tutorials, some sample papers

APA guide in the SDSU Library: Library Addition Reference, 1st floor, call # BF76.7 .P83 2020

How to cite the APA style guide:

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). 

Chicago Manual of Style

Chicago-Style Quick Citation Guide

The purpose of source citations

SDSU subscribes to the online version! Chicago Manual of Style online 

  • When accessing from outside the library you’ll need to enter you SDSU email

How to cite the Chicago manual:

The Chicago Manual of Style, 17th ed. Chicago: University of Chicago Press, 2017.

Modern Language Association Handbook 

Using MLA Format: “Get started with MLA style. Learn how to document sources, set up your paper, and improve your teaching and writing.”

How to cite the MLA Handbook:

Modern Language Association of America. MLA Handbook Eighth Edition, 2016. 

Track & organize your information sources

Keeping track of your sources can be a little challenging. There are tools that can help you stay organized. Check them out at this Research Guide: Citation Management Tools on How to Cite Your Sources

Need more information about research?

Here are some resources that will help you hone your research skills