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BIO 121 - General Biology: Cite Sources

Find resources and information to support General Biology I students.

Citing Resources


 (Council of Science Editors (CSE) 2006)


Whenever you refer to anything in writing that is another person’s work or ideas you must first paraphrase the information (write it over in your own words) and then give credit to the author by citing the source of information. Not citing your sources is plagiarism.  You must cite sources 2 ways using the Name-Year System of Citation:


  1. Parenthetically within the body of the paper
  2. In a reference section


I. PARENTHETICAL CITATIONS are in the body of the paper either at the end of the sentence in which the information is mentioned or within the sentence itself. If everything in one paragraph is from the same source you may cite that source once at the end of that paragraph.




Can be placed at the end of the sentence:


  1. source with 1 author:  (Authors last name Year)


EXAMPLE:  Blood vessels were found to be constricted (Smith 2007).


  1. Source with 2 authors: (First Authors last name and Second Authors last name Year)


EXAMPLE: Many stomata are found on leaf surfaces (Smith and Brown 1992).


  1. More than two authors: (First author’s last name and others last names Year)           or (First author’s last name et al. Year)


EXAMPLE:  Dozens of chloroplasts were within each leaf (Smith and others 1998).

 OR    Dozens of chloroplasts were within each leaf (Smith et al. 1998).


  1. Web page that is not associated with a journal article in print: (<URL>)


                  EXAMPLE:  Hearts were enlarged (< >).


OR parenthetical citations can be placed within the sentence as shown here:


  1. For sources with known authors:


                    EXAMPLES:  According to Smith (1999) the location of the mitochondria in . . .

                                              Smith and Brown (1992) found that…

  1. For work with an organization as author (Organization Year)

EXAMPLE: … as found by The Frog Conservancy (1995) tree frogs in Texas are. . .

II. REFERENCE section at the end of the paper contains the full citation, providing all the information necessary for an individual to locate that source


  1. Title this section “References”
  2. Include all author’s last names & initials (do not use “et al.”)
  3. For a single source with multiple authors, the author’s names should be listed in the same order as used in the original document.  Do not change the order!
  4. List the separate sources alphabetically by the last name of the first author
  5. Each full citation should be single spaced with a blank space between citations.
  6. Use correct order of information, punctuation and capitalization as shown in this document (CSE 2006) NOTE: quotation marks, italics, bold print and underlining are not used in the Name/Year System of Citation!!


Journal article:

First author’s last name First two initials, Subsequent author’s last names and initials separated by commas. Year of Publication.  Article title. Journal name (often abbreviated) Volume number (issue number): inclusive pages.


EXAMPLE with one author:

Sachar DB. 1994. Budesonide for inflammatory bowel disease: is it a magic bullet? N Engl J Med 331 (251):873-4.


EXAMPLE with two or more authors:

Binder V, Hendriksen C, Kreiner S. 1985. Prognosis in Crohn’s disease based on results from a regional patient group from the county of Copenhagen. Gut 26:146-50.


EXAMPLE with organization as author:

[CDFG] California Department of Fish and Game. 2002. Guidelines for evaluating marine protected areas. Journal of Fishery Science 25(2):100-122.



  1. Most journal articles can be found online.  Even if you accessed the article online as long as it is also in print you do not need to state the URL.  They are still cited as above.
  2. Don’t confuse the name of the journal with the database you used to find the article. Do not state the database you used to find the article!  



First author’s or editor’s last name First initials, Subsequent author’s or editors’ names separated by commas. Year of publication. Title of book.  Place of Publication: Publisher’s name.



Starr C, Taggart R. 2006. Biology: the Unity and Diversity of Life 11th ed.  Belmont CA: Thomson Brooks/Cole.

Unpublished Laboratory Exercise:


Author (Institution if author is unknown) Year. Title of lab exercise. Course name, Department, College or University name.



Smith J. 2008. Microorganism Lab. General Biology I, Biology Department, Manchester Community College.


Electronic Journal Articles (that are NOT in print form only available electronically):


Provide same information and format as provided for a printed journal article as shown previously.  If an article is ONLY available online (not in print form) then also add:   <URL> Accessed Year Month day. NOTE: most journal articles you will access electronically are also in print form.



Parker ET, Cleaves HJ, Dworkin JP, Glavin DP, Callahan M, Aubrey A, Lazcano A, Bada JL. 2011. Primordial synthesis of amines and amino acids in a 1958 Miller H2S-rich spark discharge experiment. PNAS 108(14): 5526-5531. <> Accessed 2013 February 2.



Internet sources: Your instructor may or may not allow you to use websites. Check with your instructor if you’re not sure! Internet sources should have an author and date. If there is no author listed use the name of the organization as the author (example: Center for Disease Control)


Authors last name & initials. Year of publication. Title. Publisher of site. <URL> Year and month accessed.



Meyer JR. 2006. Insect Physiology: Respiratory System.  North Carolina State University < > Accessed 2010 May.


Important note about URL’s:  DO NOT provide a URL link that goes through my commnet! It will only work for you, not me! Instead use a permalink that brings anyone to that web page and that does not change.  If not sure where to find the permalink, ask a librarian!


PGM 8/4/16           


What is Plagiarism?

What is Plagiarism?

Plagiarism is simply using someone's work and not acknowledging or giving credit to the original author(s).

I am plagiarizing if I:

  • Intentionally duplicate or copy another person's work including copying directly from an article, book, or website
  • Copy another student's assignment(s)
  • Paraphrase another person's work, while making only minor changes and not changing the meaning or ideas presented by the original author(s)
  • Copy sections of another person's work and piece these sections together to create a new whole
  • Turn in an assignment that has been previously submitted for assessment and then take credit for the assignment
  • Turn in an assignment as independent work when the assignment was produced in whole or part in collusion with another student(s), tutor(s), or person(s)

For more information regarding Plagiarism visit:

How to Evaluate Web Sites

Learn to be critical thinkers. When conducting research on the World Wide Web, evaluate the sites you are viewing using the criteria found in this section.

·         ACCURACY     Anyone can publish information on the web. The information may or may not be accurate. Most web sites are not verified by editors and fact checkers. Look for e-mail, contact address and phone numbers. You want to find out if the author is qualified to write the web page.


·         AUTHORITY     Web sites should enable the researcher to find out about the authors. Look for names, where they work, credentials, addresses, and e-mail addresses. Look for the URL domain. Is the author affiliated with an educational institution (edu), a government agency (gov), an organization (org), or a commercial site (com)? Do the authors/publishers list their qualifications?


·         OBJECTIVITY     Are the goals and aims of the persons or groups responsible for the web site clearly stated? Is the group/person/organization legitimate? Some sites are thinly disguised commercials or opinion pages. Does the author express his/her opinions? Ask yourself why the page was written and for whom.


·         CURRENCY     Dates are not usually included on web pages. Check for dead links and outdated information. If you see a date listed, it may be the date of posting or the date of revision.


·         COVERAGE     Are you getting all the information this site has to offer? Do you need specialized software to access the information? Are you required to pay a fee to access the information? Is the content of the web page balanced with text and graphics? Are links relevant to the document’s content? Good web sites should contain a statement explaining or summarizing topics covered on the site.


PC 7/98, 1/06