UMGC Library

APA 6th Edition Citation Examples: E-books

Library database with DOI

Chaffe-Stengel, P., & Stengel, D. (2012). Working with sample data: Exploration and inference.

What is a DOI?
Some library databases, such as Academic Search Ultimate and APA PsycInfo, list a Digital Object Identifier (DOI) for individual e-books. A DOI is a unique identifying number for an e-book. In the database record for an e-book, you will see an element that looks like this, which you should include at the end of your APA reference, preceded by "":

Digital Object Identifier

This link will allow a reader to link to for more information about the e-book.

Library e-book database without DOI

Miller, L. (2008). Careers for nature lovers & other outdoor types. Retrieved from

No DOI? Use the URL for the database.
When a book has no DOI, write “Retrieved from” followed by the URL of the database. Use these URLs for library e-book databases:

  • EBSCO eBooks Collection:
    Retrieved from
  • Safari Books Online:
    Retrieved from
  • Books 24x7:
    Retrieved from

Book read on an e-book reader

Gladwell, M. (2008). Outliers: The story of success [Kindle DX version]. Retrieved from

After the book title, put in brackets the name of the e-book reader, with the word “version.” Follow that with the DOI. If the book has no DOI, write “Retrieved from” followed by the URL of the site from which you downloaded the e-book.

Free Web

Seton, E. T. (1911). The Arctic prairies: A canoe-journey of 2,000 miles in search of the caribou. Retrieved from

Book chapter from a library database (suggested format)

Quina, K., & Kanarian, M. A. (1988). Continuing education. In P. Bronstein & K. Quina (Eds.), Teaching a psychology of people: Resources for gender and sociocultural awareness (pp. 200-208). Retrieved from

When using just a chapter from a book the same rules apply regarding DOI or no DOI as listed above, depending on where the book was retrieved.

More info

See Style Guide, pp. 15-18.