AMA Style: The Basics for Pharmacy Writing: E-book (online book)

Note: Pay attention to capitalization in book titles.  

Author(s). Book Title. Edition number (do not indicate 1st edition). Publisher’s name; most recent copyright year. Accessed date. URL (no period after the URL)

Example

1. Olsen CG, Tindall WN, Clasen ME. Geriatric Pharmacotherapy: A Guide for the Helping Professional. American Pharmacists Association; 2007. Accessed February 27, 2020. https://online.statref.com/Document.aspx?docAdd ress=b722bOI4Cx5PboVh08z