Citing sources for a book is crucial for nonfiction authors striving for accuracy and credibility in their work. Navigating the maze of various citation styles, like APA, MLA, Chicago, and Harvard, can be daunting, but mastering them is essential for any aspiring author. If you find yourself floundering between citation styles, or just curious about your options, read on.

Why Do Citations Matter?

Citations are the backbone of nonfiction writing and serve several key purposes: 

  • They provide a way to give credit to the people, ideas, and information you incorporate into your work. This isn’t just an ethical requirement for authors; it’s a legal one that protects you against plagiarism claims.
  • The use of citations also enhances the credibility of your work by helping readers see the foundation of your arguments and trust the accuracy of your information. 
  • Well-cited work allows readers to further explore the subject matter, making your writing a valuable resource in the larger academic conversation.

Know Your Citation Format Options

For most nonfiction authors, it’s a matter of choice between the two most common citation styles. The Chicago style, coined by the Chicago Manual of Style, is the most commonly used thoughout the publishing industry. However, APA format, established by the American Psychological Association is widely used in academic writing.

Which Citation Style Is Right for Me?

If your work includes extensive historical research or draws from a variety of source types, Chicago style might be a better fit. This is especially true for texts that benefit from explanatory notes like footnotes, as the Chicago Style has that option. 

On the other hand, if your writing is research-oriented and focuses on timely, data-driven studies, the APA format could be more appropriate for your book. This style is also beneficial when your audience is likely to be familiar with the latest research in psychology, education, or the social sciences.

Chicago Style Citations

Notes-Bibliography

Chicago style citations come in two flavors: Notes-Bibliography (NB) and Author-Date. The NB system is mainly seen where source commentary is common such as literature and the arts. In this system, you use footnotes or endnotes for citation, with each note corresponding to a superscript number in the text. A bibliography at the end of the document lists all sources.

A footnote typically includes the author’s full name, the source title, the publication place and date, and the page number if it’s a direct quote. For instance: 

  • ^1John Smith, Climate Change and Our Future (New York: Eco Press, 2020), 78.

Author-Date 

The Author-Date system, similar to APA described below, is used in the sciences and social sciences. In this style, in-text citations include the author’s last name and the year of publication, with a reference list at the end for full details of every source. 

Both systems require attention to detail to ensure accuracy and readability for your reader.

Bibliography Page

In the Chicago Notes-Bibliography system, the bibliography page is where you compile all sources you’ve cited in the footnotes or endnotes. Unlike a reference list in the Author-Date system, the bibliography provides complete citations in a format that allows for greater detail and, at times, commentary.

Each entry starts with the author’s last name, followed by their first name. For books, the title of the work is italicized while articles are placed within quotation marks. Publication information comes next, including the publisher, publication year, and pages used. 

For example: Smith, John. The Warming Globe: Risks and Adaptations. Chicago: Earthwise Press, 2020, pg. 19-24.

Journal articles follow a similar format, with the article title in quotations, followed by the journal name in italics: Jones, Linda. “Forests and Carbon Sequestration.” Environmental Studies Quarterly 34, no. 2 (2021): 123-145.

APA Citations

When using APA style,your in-text citations and reference list entries should correspond accurately. Each in-text citation should quickly direct your readers to the full citation in your reference list, which provides all the necessary information to locate the original source.

In-Text Citations

In APA style, in-text citations are used to give credit when you have used someone else’s ideas or words and help readers locate the full citation on your references page. 

For direct quotes, APA style requires you to include the page number or paragraph number from the original source you took the quote from. 

  • For example, (Smith, 2020, p. 15) or (Smith, 2020, para. 4). 

When paraphrasing, page numbers are not mandatory, but you may include them to guide readers to the exact spot in the source.

  • Example: (Smith, 2020, p. 15).


If you use a source without a known author, you can use the title of the work or a shortened version of the title and the year of publication.

  • Example: (“Study of Climate,” 2021). 

For electronic sources lacking page numbers, use the paragraph number or a heading and the paragraph number under that heading. 

  • (Smith, 2020, “Climate Change,” para. 3). Chicago Style Citations

Reference Page

In APA citation style, the reference page has its own set of rules to ensure that each citation provides sufficient information on the source material. The list is alphabetized by authors’ last names and formatted with a hanging indent. Each entry typically includes the author’s last name, first initials, publication year, title of the work, and publication or retrieval information.

For example…

  • A book citation would look like: 
    • Smith, J. (2020). Climate Change and You. Green Earth Publishing.
  • Citations for articles from online journals or sources should include a DOI (Digital Object Identifier) or URL if available. 
    • For example: Jones, L., & Taylor, M. (2021). The Impact of Reforestation. Journal of Environmental Studies, 13(2), 234-250. https://doi.org/xx.xxx/yyyy
  • For sources without an author, the title moves to the author’s position: 
    • Study of Climate Patterns. (2021). Environmental Research Letters, 16(1), 5-13.

Consistency Is The Most Important

  • Self-published authors have the option to choose their citation format, which means the most important thing is to pick one and remain consistent. Whichever option you choose, use this guide to keep you on track.

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