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College Writing 161: Writing in the Biological Sciences: Cite sources

Guide to finding, reading, evaluating, saving and organizing different types of writing in the biological sciences.

Why cite your sources?

Why cite your sources?

The communication of scientific research results through articles, books, and other forms of writing can be thought of as a kind of conversation. Citing your sources:

  • enables your readers to follow the "conversation" by going back to the sources you are drawing on in your work to understand the background for your contribution;
  • allows your readers to weigh and evaluate the evidence you are presenting;
  • shows that you are familiar with the work others have done in the area you're writing about;
  • gives previous contributors to the "conversation" proper credit for their work.

Citation elements

Citation elements

Citations should include enough information to enable someone else to find your source. The basic elements of a citation to an article include:

  1. Author name(s): the names of the authors of the article
  2. Publication year: the year the article was published
  3. Article title (e.g., "Approaching a state shift in Earth's biosphere")
  4. Journal title: the name of the journal in which the article was published (e.g., Nature, Ecology, or Journal of Arid Enviroments)
  5. Volume number: journals are often divided into volumes that indicate that they have been published in a specific time period (e.g., if the volume numbers change annually, "volume 17" would indicate that the issues in that volume were published in the journal's 17th year of publication). Volume numbers for different journals can change after different time periods: annually, semiannually, quarterly, or even monthly.
  6. Issue number (omitted for many citation styles in the sciences): Each volume is often subdivided into specific groupings of articles that are published at regular intervals (e.g., if the journal is published monthly, issue 1 may include the articles published in January, issue 2 the articles published in February, etc.).
  7. Page numbers (for articles published both in print and online) or article number (for online-only articles)
  8. For articles published online: URL or DOI (omitted for some citation styles)

What is a DOI?
Find an article using a DOI:
Try this example:

Freeman LA, Kleypas JA, Miller AJ. 2013. Coral reef habitat response to climate change scenarios. PLoS ONE 8: e82404. doi:10.1371/journal.pone.0082404

Click on the "Find an article using a DOI" link above, copy and paste the DOI into the "Resolve a DOI" box, and click "Go." (Don't include "doi:") Were you able to access this article?

Citation styles

Citation Styles

A citation style is a specific way in which the elements of a citation are combined and formatted. There are hundreds of different citation styles.

For your assignments in CW 161 you are asked to use one of three different citation styles, depending on your topic and your major area: AMA (American Medical Association), APA (American Psychological Association), or CSE (Council of Science Editors).

Here are examples of in-text and reference list citations to a journal article in each of the three styles:

AMA

  • In-text citation: Residential segregation impacts the ecology of urban landscapes.1
  • Reference list citation:
  • 1. Schell CJ, Dyson K, Fuentes TL, et al. The ecological and evolutionary consequences of systemic racism in urban environments. Science. 2020;369(6510):eaay4497. doi:10.1126/science.aay4497.

APA

  • In-text citation: Residential segregation impacts the ecology of urban landscapes (Schell et al., 2020).
  • Reference list citation:
  • Schell, C. J., Dyson, K., Fuentes, T. L., Des Roches, S., Harris, N. C., Miller, D. S., Woelfle-Erskine, C. A., & Lambert, M. R. (2020). The ecological and evolutionary consequences of systemic racism in urban environments. Science, 369(6510), eaay4497. https://10.1126/science.aay4497

CSE name-year

  • In-text citation: Residential segregation impacts the ecology of urban landscapes (Schell et al. 2020)
  • Reference list citation:
  • Schell CJ, Dyson K, Fuentes TL, Des Roches S, Harris NC, Miller DS, Woelfle-Erskine CA, Lambert MR. 2020. The ecological and evolutionary consequences of systemic racism in urban environments. Science. 369(6510):eaay4497.

Citation managers

Citation managers (also called reference managers or bibliographic management software) offer a way to save, organize and manage references. Many work with word processing software to format in-text citations and bibliographies for papers and theses, allow you to share references, and enable you to attach or link PDFs to a citation record.

Wikipedia comparison of reference management software

Selected citation managers (there are many more):

  • Zotero guide [UC Berkeley Library]
  • Zotero documentation [Zotero.org]
  • Free Zotero workshops [UC Berkeley Library]
  • Free desktop program with browser connector; 300 MB storage (can be synced with Google Drive, Berkeley Box or Dropbox for greater storage--see Zotero guide for details)
  • Sync Zotero to access your library from any computer with internet access
  • Insert citations and automatically format reference lists in Google Docs/bDrive, MS Word and LibreOffice
  • Capture citation data from PDFs and web pages
  • Share and collaboratively edit folders of references
  • Mendeley guide [UC Berkeley Library]
  • Free software/web hybrid for PC, Mac, Linux; 100 GB web storage for UC Berkeley Institutional Group members
  • Format bibliographies in MS Word or OpenOffice
  • Sync PDFs to your web account for online access
  • Capture citation data from some PDFs
  • Read and annotate PDFs
  • Share and collaboratively edit folders of references
  • RefWorks guide [UC Berkeley Library]
  • Free to UC Berkeley users; unlimited storage
  • Web-based: use at any computer with internet access
  • Insert citations and automatically format reference lists in Google Docs/bDrive and MS Word
  • Import citations from RSS feeds
  • Use UC-eLinks to find the full text of articles from within RefWorks
  • Capture citation data from PDFs and web pages
  • Read and annotate PDFs
  • Share and collaboratively edit folders of references
  • Papers guide
  • Software/web hybrid for Mac and Windows available by subscription
  • Format bibliographies in MS Word and Pages
  • Automatically import PDFs together with citation
  • Search, highlight and annotate PDFs
  • EndNote guide [UC Berkeley Library]
  • Discounted to UC Berkeley users [please contact me for details]
  • Desktop-based software (plus EndNote Web)
  • Format bibliographies in MS Word or OpenOffice
  • Capture citation data from some PDFs
  • Annotate PDFs
  • Use UC-eLinks to find the full text of articles from within EndNote
  • Share lists of references with other EndNote users

For more help

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Elliott Smith
Contact:
Bioscience, Natural Resources &
Public Health Library
esmith@library.berkeley.edu