To create a bibliographic reference for an OpenStax textbook, follow this pattern:
Author(s). (Year). Title. Publisher. URL or DOI
Here's a sample Reference Citation for the OpenStax Biology 2e textbook:
References
Clark, M. A., Douglas, M., & Choi, J. (2018, March 28). Biology. OpenStax. https://openstax.org/details/books/biology-2e.
Here, the authors' last name, first & (if included) middle initials are included. The copyright date (year) and the URL can be found on the copyright statement page of the PDF of the e-textbook.
If you redistribute this textbook, part of this textbook, or images from this textbook in a print format, these authors request you include on every physical page using content from this source the following attribution:
If you have a link to the e-textbook in your class, and it opens in your browser (and not in a PDF), then the copyright date may be different. To find the correct copyright date for the web-based version of the textbook, go to the Table of Contents area, select "Preface" and then look for the "Attribution" section (it may be all the way at the bottom of the page). The copyright date should be located there.