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Cite a Source

Citing Sources

Citing is the process of giving credit to the sources you used to write your paper. Citations can be located in the text or at the end of the work in a bibliography. It can be difficult to figure out what needs to be credited.

Quick Links:

APA Style

Widely used in psychology, education, and other social sciences

MLA Style

Used in literature, arts, and humanities

AMA Style

Required style for medicine, health, and biological sciences

Turabian Style

Specifically designed for college students to use with all subjects

Chicago Style

Commonly used in history, humanities, and non-scholarly publications

What is Citing?

Citing is the process of giving credit to the sources you used to write your paper. Citations can be located in the text or at the end of the work in a bibliography.   It can be difficult to figure out what needs to be credited. 

Use this rule of thumb: If you knew a piece of information before you started doing research, generally you do not need to credit it. You also do not need to cite well-known facts, such as dates, which can be found in many encyclopedias. All other information such as quotations, statistics, and ideas should always be cited in your papers.


Duplicate publication, sometimes called self-plagiarism, occurs when an author reuses substantial parts of his or her own published work without providing the appropriate references.

from Rosenzweig, Merle, and Anna Ercoli Schnitzer. "Self-plagiarism Perspectives for librarians." College & Research Libraries News 74, no. 9 (2013): 492-494 (link to article).

While the above quote mostly addresses published works and is therefore more a matter of copyright, it is considered plagiarism to submit the same work or paper for two or more classes. If you wish to submit a paper written in one class for credit in another class you must obtain permission from the both the instructor of the original course and the instructor of the current course before submitting the same, or substantially similar, paper. Failure to do so is plagiarism and academic fraud, and may lead to disciplinary action.

Editorial Style

Editorial style, also known as style guides or style manuals, are the guidelines that ensure papers and other documents are presented in a consistent format to ensure clear and consistent presentation of written material. Editorial style concerns uniform use of such elements as:

  • punctuation and abbreviations
  • construction of tables
  • selection of headings
  • citation of references
  • presentation of statistics
  • and other elements of every manuscript.

(from The American Psychological Association Style site)

Managing your sources

There are many different citation managers that can help you organize your citations and build bibliographies. Solutions include Zotero, a free Firefox extension that is great for capturing and archiving screenshots, Mendeley, a citation manager that is particularly good at managing .pdf files, and EndNote, a manager that is used heavily in the sciences. Most citation managers offer options like organizing citations into folder, building bibliographies, attaching files and links, and sharing your citations with others.  Compare all citation managers.

Citation Managers

>> Download this graphic as a .pdf file. Or  Compare all citation managers.

Print Style Manuals

The complete hardcopy style manuals contain examples about citing a wider variety of sources than these web pages do, as well as other things you may need to know, such as margins, font size, etc. You can find style manuals in the following library locations: 


Style Manual

Call Number


The ACS Style Guide: A Manual for Authors and Editors [Chemical], 2nd ed.

808.06654 AC781997

Chemistry Library, Geology Reference

American Medical Association Manual of Style, 10th ed. 

610.149 Am3s2007

Veterinary Med Reference, Main Reference

The Chicago Manual of Style, 15th ed.

655.25 C43m2003

Main Reference, Undergraduate Library, most departmental libraries

The Complete Guide to Citing Government Documents

016.015 G186C1993

Main Reference, Main Stacks, Oak Street

A Manual for Writers of Term Papers, Theses, ... [Turabian], 6th ed.

808.02 T84M1996

Main Reference, Undergraduate Library, some departmental libraries

The MLA Style Manual and Guide to Scholarly Publishing, 3rd ed.

808.02 Ac47m2008

Main Reference (Info Desk), English Reference

The MLA Handbook for Writers of Research Papers, 7th ed.

808.02 M72m1 2009

Main Reference, Undergraduate Reference

Publication Manual of the American Psychological Association, 6th ed.

029 AM4P 2010

Main Reference (Info Desk), Undergraduate Library, Education Reference, some departmental libraries

Scientific Style and Format : The CBE Manual for Authors, Editors, and Publishers, 6th ed.

029.6 C76S1994

Biology Reference, Natural History Reference, Vet. Med. Reference


More information on citing sources

Based on: http://www2.liu.edu/cwis/cwp/library/workshop/citation.htm   Long Island University, Robert Delaney