3-20 authors
Include all of the authors' names (up to 20 names), inserting an '&' before the last name.
Ex. Author, A. A., Author, B. B., & Author, C. C. (Year). Title of book. Publisher.
More than 20 authors
Include a total of 20 names in a reference. Enter the first 19 names, after which use ... and enter the last author's name.
Ex. Author, A. A., Author, B. B., & Author, C. C. … Author, Z.Z. (Year). Title of book. Publisher.
3+ authors
(Author et al., Year)