Annotated Bibliography Examples: APA, MLA, Chicago

An annotated bibliography is a list of sources with a brief annotation after each entry. The annotation describes the source, evaluates its credibility and relevance, and explains how it contributes to your research. It is not simply a summary; it demonstrates that you have read, evaluated, and can situate each source within your project.

This page shows complete annotated bibliography examples in APA, MLA, and Chicago format, with labels explaining what each element of the annotation does.

What a Good Annotation Contains

Most annotations have two to three components:

Some assignments ask for descriptive annotations (summary only) rather than evaluative ones. Check your assignment instructions.

APA Format Annotated Bibliography Examples

In APA format, the bibliography is titled "Annotated References" or "Annotated Bibliography." Entries follow standard APA 7th edition format, with the annotation indented below the citation.

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Entry 1:

Twenge, J. M., Haidt, J., Joiner, T. E., & Campbell, W. K. (2020). Underestimating digital media harm. Nature Human Behaviour, 4(4), 346–348. https://doi.org/10.1038/s41562-020-0839-4

[SUMMARY] This commentary argues that social science researchers have systematically underestimated the harm of digital media on adolescent mental health by applying inappropriately strict statistical thresholds and focusing on average effects that obscure harm to vulnerable subgroups. The authors contend that a dose-response relationship between heavy social media use and depression is consistent across data sources and that the magnitude of harm is comparable to other risk factors taken seriously in public health.

[EVALUATION] The authors are prominent scholars in psychology and social science, and the piece is published in a high-impact peer-reviewed journal. However, this is a commentary, not a primary study, and reflects the authors' position in an ongoing academic debate rather than presenting new data. The piece should be read alongside opposing viewpoints (e.g., Orben & Przybylski, 2019) to understand the methodological disagreement it addresses.

[RELEVANCE] This source provides the theoretical basis for expecting a meaningful relationship between social media use and adolescent mental health and directly motivates the methodological choices of the present study.

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Entry 2:

Coyne, S. M., Rogers, A. A., Zurcher, J. D., Stockdale, L., & Booth, M. (2020). Does time spent using social media impact mental health? An eight year longitudinal study. Computers in Human Behavior, 104, 106160. https://doi.org/10.1016/j.chb.2019.106160

[SUMMARY] This eight-year longitudinal study tracked social media use and mental health outcomes in 500 adolescents from early to late adolescence. Contrary to many cross-sectional studies, the authors found no significant longitudinal association between social media use and depression, anxiety, or internalizing symptoms. They emphasize the importance of using longitudinal designs and validated clinical measures rather than single-item self-report outcomes.

[EVALUATION] The longitudinal design and validated outcome measures are methodological strengths that address limitations of cross-sectional research. However, the study relies on self-reported social media use and does not distinguish between passive and active use types, a distinction highlighted as important in other research. The null finding may partly reflect these measurement issues.

[RELEVANCE] This source represents the competing view that social media does not predict mental health outcomes in longitudinal designs, and it motivates the present study's focus on passive versus active use distinctions as a potential explanation for inconsistent findings in the literature.

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MLA Format Annotated Bibliography Examples

In MLA format, the bibliography is typically titled "Annotated Works Cited." Entries follow MLA 9th edition format.

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Entry 1:

Morrison, Toni. Beloved. Alfred A. Knopf, 1987.

[SUMMARY] Morrison's novel depicts the psychological and physical aftermath of slavery through the story of Sethe, a formerly enslaved woman haunted by the ghost of her daughter. The novel draws on historical records of Margaret Garner, who killed her infant daughter in 1856 rather than allow her to be returned to slavery. Morrison uses fragmented chronology and an unreliable narrator to represent how trauma disrupts coherent memory and narrative.

[EVALUATION] Beloved is among the most studied American novels of the 20th century and is frequently taught as a primary text for examining slavery's psychological legacy. It is not a historical source in the documentary sense but rather an artistic interpretation that has shaped critical discourse on trauma, memory, and African American literary representation for decades.

[RELEVANCE] This novel provides the primary textual evidence for the paper's argument that Morrison represents trauma as a force that restructures time and identity rather than a historical event that can be integrated into conventional narrative. Key passages from chapters 2 and 19 are analyzed in detail.

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Entry 2:

Hartman, Saidiya. Scenes of Subjection: Terror, Slavery, and Self-Making in Nineteenth-Century America. Oxford University Press, 1997.

[SUMMARY] Hartman's foundational study examines the legal, cultural, and performative structures through which slavery produced the enslaved as subject. The book focuses on the concept of "coerced will": the mechanisms by which slaveholders and legal institutions forced enslaved people to perform consent and pleasure, obscuring the violence of the system while making it self-sustaining.

[EVALUATION] This is a highly cited work in African American studies and legal history. Hartman's close reading of legal archives and performance theory is methodologically rigorous, though some historians have questioned her interpretations of specific legal cases. The book's influence on subsequent scholarship is extensive and well-documented.

[RELEVANCE] Hartman's concept of coerced will provides the theoretical framework for this paper's reading of the "pleasure" scenes in chapters 4 and 8 of Beloved as representations of exactly the kind of forced performance Morrison's novel critiques. Her analysis complements Paul Gilroy's work on the Atlantic slave trade as a counternarrative to Western modernity.

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Chicago Format Annotated Bibliography Examples

In Chicago Notes-Bibliography style, the annotated bibliography follows standard bibliography formatting, with annotations indented below each entry.

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Entry 1:

Jackson, C. Kirabo, Rucker C. Johnson, and Claudia Persico. "The Effects of School Spending on Educational and Economic Outcomes: Evidence from School Finance Reforms." Quarterly Journal of Economics 131, no. 1 (2016): 157–218.

[SUMMARY] Using variation in school spending driven by court-ordered school finance reforms as an instrument for causal identification, this study finds that a 10 percent increase in per-pupil spending throughout the school years leads to 7 percent higher adult wages, lower rates of adult poverty, and higher educational attainment. Effects are largest for students from low-income families, suggesting that additional resources matter more for disadvantaged students.

[EVALUATION] The instrumental variables design addresses a key threat to causal inference (that school spending and student outcomes are both driven by unobserved local factors), making this one of the most methodologically credible studies in the school finance literature. The study's primary limitation is that it cannot identify which specific uses of increased spending drive the outcomes; it establishes that money matters but not precisely how.

[RELEVANCE] This study provides the foundational empirical evidence for the paper's argument that court-ordered finance reforms can improve outcomes, and motivates the investigation of governance capacity as a moderator of the spending-outcome relationship. It is the most-cited piece in the paper's literature review.

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How to Write an Annotation

Step 1: Read the source carefully. You cannot write an accurate annotation without reading the source in full, or at minimum reading the abstract, introduction, and conclusion carefully.

Step 2: Write the summary first. In two to four sentences, state: what the source argues or finds, the evidence or approach it uses, and the main conclusion. Do not include every detail.

Step 3: Evaluate the source. Address: What is the author's expertise or the publication's credibility? What are the study's methodological strengths or limitations? Is the evidence strong enough to support the conclusions? Are there important counterarguments the source does not address?

Step 4: State its relevance to your project. Explain specifically how this source contributes to your research: what claim it supports, what gap it fills, what theoretical framework it provides, or how it fits in relation to other sources you are using.

Step 5: Check the length. Most annotations are 100 to 200 words per entry. Check your assignment instructions, as some require shorter descriptive annotations (summary only, 50 to 75 words) or longer evaluative annotations (up to 300 words).

Common Mistakes

Summarizing without evaluating. A descriptive annotation lists what the source says. An evaluative annotation assesses its quality and usefulness. Unless the assignment specifies descriptive only, include evaluation.

Too much summary, not enough relevance. Many students write three or four sentences of summary and one sentence of vague relevance ("This source will be useful for my paper"). Be specific: state which part of your argument this source supports and why it is more useful than alternatives.

Praising every source. Not all sources are equally strong. An evaluative annotation that identifies a limitation or notes a methodological weakness demonstrates more critical reading than one that calls every source "reliable and informative."

Formatting inconsistency. Citation format must match the required style exactly (APA, MLA, Chicago). The annotation is indented below the citation, not merged with it.

Frequently Asked Questions

What is an annotated bibliography? An annotated bibliography is a list of sources in which each citation is followed by a brief annotation describing, evaluating, and situating the source. It demonstrates that you have read and assessed each source, not just collected citations. Most annotations are 100 to 200 words and include a summary of the source, an evaluation of its credibility and methodology, and an explanation of its relevance to your research.

What is an example of an annotated bibliography entry? An APA annotated bibliography entry begins with the standard citation, then the annotation below it: "Twenge, J. M., et al. (2020). Underestimating digital media harm. Nature Human Behaviour, 4(4), 346–348. [Annotation follows.] This commentary argues that researchers have underestimated digital media harm by applying overly strict statistical thresholds. Published in a high-impact peer-reviewed journal. Provides theoretical grounding for the present study's hypothesis that social media affects mental health."

How long should an annotated bibliography annotation be? Most annotations are 100 to 200 words. Some assignments specify shorter annotations (50 to 75 words for purely descriptive annotations) or longer ones (250 to 300 words for in-depth evaluative annotations). Check your assignment instructions for the specified length and format.

What is the difference between a bibliography and an annotated bibliography? A regular bibliography or reference list contains only the formatted citation for each source. An annotated bibliography contains the same citations plus a paragraph after each one evaluating the source and explaining its relevance. An annotated bibliography requires significantly more engagement with each source than a standard bibliography. For more on the difference between bibliography types, see bibliography vs works cited.

Do you need an annotated bibliography for every paper? No. Annotated bibliographies are assigned as specific exercises to develop source evaluation skills, or are required for specific research projects (thesis proposals, grant applications, literature reviews). They are not a standard component of every research paper. Most papers end with a regular references page or works cited list.

For related research and citation guidance, see how to write a literature review, bibliography vs works cited, and how to cite a book.