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Science 311

When citing...

... you acknowledge another person's ideas, whether you have quoted them directly or not. You are also trying to provide enough information for your reader to find the source that you consulted.

A citation provides brief details of the author and date of publication within your paper. It leads the reader to your Bibliography or Reference List

A Bibliography or Reference List is a list at the end of your paper of all references used within your paper

  • APA style: references are sorted alphabetically by surname of the first author

A reference is a specially formatted description of the item from which you obtained your information

APA Style

For this course, we use APA (American Psychological Association) style, 7th edition. The full APA style manual is available in print from the library or bookstore, but for the purposes of this course you should be able to find enough guidance using these sources.

TIP -- Multiple authors: 

  • If there are 2 authors, include both authors in your in-text citation AND in your bibliography.
  • If there are 3-20 authors, list only the first author in your in-text citation, followed by "et al.", and list ALL authors in the end reference list
  • If more than 20 authors, list only the first author in your in-text citation, followed by "et al.", then list the first 19 authors in the end reference list, then an ellipsis (...) after the 19th author, then finish the list with the final author. 
  • Purdue OWL guidance - In-text citations: Author/Authors
  • Purdue OWL guidance - Reference List


  • If using Zbib or another citation software program, you should be able to select APA 7 as your style.
  • Note that Zbib is only as good as the data that goes into it. It's your responsibility to check the references it generates and correct any errors. Common errors can occur with authors who have two surnames or with improper capitalizations of proper nouns such as corporate and place names.