How to write an annotated bibliography

What is an annotated bibliography?

An annotated bibliography or annotated bib is a bibliography (a list of books or other works) that includes descriptive and evaluative comments about the sources cited in your paper. These comments are also known as annotations.

How do I format my annotated bibliography?

An annotated bibliography entry consists of two components: the Citation and the Annotation.


The citation should be formatted in the bibliographic style that your professor has requested for the assignment. Some common citation styles include APA, MLA, and Chicago. For more information, see the Style Guides page.


Generally, an annotation is approximately 100-300 words in length (one paragraph). However, your professor may have different expectations so it is recommended that you clarify the assignment guidelines.

An annotation may include the following information:

  • A brief summary of the source
  • The source’s strengths and weaknesses
  • Its conclusions
  • Why the source is relevant in your field of study
  • Its relationships to other studies in the field
  • An evaluation of the research methodology (if applicable)
  • Information about the author’s background
  • Your personal conclusions about the source

MLA style format (9th ed.)

Refer to Section 5.132, p. 226 in the MLA Handbook, 9th ed. [print] [online] for detailed information on annotated bibliographies.

The following are general guidelines. Check with your instructor for specific formatting instructions regarding your assignments.

Format the source just as you would in a works cited list: follow the MLA template of core elements and use a half-inch hanging indent for all subsequent lines following first line of the citation [Section 5.1-5.2, pp. 105-107; Appendix 2, pp. 313-346]. Add the annotation below the citation, indented another half-inch to differentiate it from the citation. Annotations should generally be no more than one paragraph. If multiple paragraphs are necessary, indent each one but do not add an extra space between paragraphs. Title your list as Annotated Bibliography or Annotated List of Works Cited.   

Lozier, Jeffrey D., et al. "Predicting the Distribution of Sasquatch in Western North America: Anything Goes with Ecological Niche Modelling." Journal of Biogeography, vol. 36, no.9, 2009, pp. 1623-1627. JSTOR,

This paper critiques the use of Ecological Niche Models (ENM) and species distribution by performing a tongue-in-cheek examination of the distribution of the fictional Sasquatch, based on reports from an online Bigfoot archive. Lozier's paper powerfully demonstrates the issues faced by ENM, when reports come from non-specialists, and highlights key problems with sourcing data from unmediated online environments. The author neglects to compare the reliability of the many wildlife databases with the single Bigfoot database, as well as other key issues; however in closing, the paper briefly mentions that many issues lie outside the scope of the short article. Lozier's paper advises professionals in fields using ENM to carefully assess the source of the data on which the model is based and concludes that the distribution of rare species in particular is often over-reported to misidentification.

APA style format (7th ed.)

Refer to Section 9.51, p. 307 and Figure 9.3, p. 308 in the Publication Manual of the American Psychological Association, 7th ed. [print] for detailed information on annotated bibliographies.

The following are general guidelines. Check with your instructor for specific formatting instructions regarding your assignments.

References follow the same alphabetical order as entries in a reference list [Section 9.43-9.44, p. 303]. The annotation is a new paragraph below its reference entry and follows block quotation format [Section 8.27, pp. 272-273]. Should the annotation have multiple paragraphs, the first line of the second and subsequent paragraphs are indented an additional 0.5in.

D’Elia, G., Jorgensen, C., Woelfel, J., & Rodger, E. J. (2002). The impact of the Internet on public library use: An analysis of the current consumer market for library and Internet services. Journal of the American Society for Information Science and Technology, 53(10), 808-820.
In this study, the researchers examined if the Internet had affected public library usage in the United States. This study is distinct because its researchers surveyed library nonusers as well as   users. The major finding was that 75.2% of people who used the Internet also used the public library. However, the researchers surveyed only 3000 individuals in a population of millions; therefore, these results may not be statistically significant. However, this study is relevant because it provides future researchers with a methodology for determining the impact of the Internet on public library usage.

Additional resources

Writing an annotated bibliography
From Concordia University

How to prepare an annotated bibliography
From Cornell University

Writing an annotated bibliography
From University of Toronto

Annotated bibliographies
From The Writing Center at the University of North Carolina at Chapel Hill