Skip to Main Content

Citing Digital Libraries: e-Books

How to Guide for citing sources from digital libraries.

e-Book Collections

Recognizing When to Cite an Online Book as an e-Book

bitmoji graphic


  1. The book will be available as a iconpdf or icon epub document.
  2. Often, the pages will display like pages of a book, even if there are no page numbers.
  3. The book will include the front page of the book containing publication information, i.e. Title, Author, Location, Publisher, and Year.
  4. If the book is displayed in html format, as found on and, follow the rules for citing website content.
  5. If a book has been specifically formatted for an academic research platform, such as Gale eBooks, Oxford Reference, or Theology and Religion Online, follow the rules for citing a chapter of other part of an edited book and include all the elements for citing an e-book.

Guidelines for Citing Online Books as e-Books

  1. Cite books consulted online as e-books.
  2. Whether from the CDU Online Library's e-book collections in ATLa or EBSCO, or from a free internet resource, such as those listed below, books consulted online should include a URL or the name of the database.
  3. Books formatted for Kindle, Nook, or other specific e-readers, should include the name of the format.
  4. If no fixed page numbers are available, cite a section title or chapter number, if available; otherwise, omit.

Special Exceptions

The Bible, the Catechism, Church Documents, and the Summa are cited using parenthetical (in-text) citations in place of footnotes, even when cited from online sources. 

List the Bible, the Catechism, Church Documents, or the Summa in your bibliography based on the format of the online source you consulted, e-book or website content.

Online Sources for e-Books

These citation rules apply to books accessed from the following sources.

Citation Quick Guides

Citation & Bibliography Examples: e-Books


1. Herman Melville, Moby-Dick; or, The Whale (New York: Harper & Brothers, 1851), 627,

2. Philip B. Kurland and Ralph Lerner, eds., The Founders’ Constitution (Chicago: University of Chicago Press, 1987), chap. 10, doc. 19,

3. Brooke Borel, The Chicago Guide to Fact-Checking (Chicago: University of Chicago Press, 2016), 92, ProQuest Ebrary.

4. Jane Austen, Pride and Prejudice (New York: Penguin Classics, 2007), chap. 3, Kindle.

Shortened Footnotes

5. Melville, Moby-Dick, 722–23.

6. Kurland and Lerner, Founders’ Constitution, chap. 4, doc. 29.

7. Borel, Fact-Checking, 104–5.

8. Austen, Pride and Prejudice, chap. 14.

Bibliography Entries (in alphabetical order)

Austen, Jane. Pride and Prejudice. New York: Penguin Classics, 2007. Kindle.

Borel, Brooke. The Chicago Guide to Fact-Checking. Chicago: University of Chicago Press, 2016. ProQuest Ebrary.

Kurland, Philip B., and Ralph Lerner, eds. The Founders’ Constitution. Chicago: University of Chicago Press, 1987.

Melville, Herman. Moby-Dick; or, The Whale. New York: Harper & Brothers, 1851.

Examples courtesy of the  Chicago Manual of Style Online.

For more examples, see 14.159–63 in The Chicago Manual of Style.