Two authors: use both surnames every time, joined by “and” in narrative text or “&” in parentheses
Three or more authors: use the first author’s surname followed by “et al.” every time
In-text citation format for two authors: (Smith and Jones, 2020)
In-text citation format for three or more authors: (Smith et al., 2020)
Parenthetical citation with two authors: (Smith & Jones, 2020)
Parenthetical citation with three or more authors: (Smith et al., 2020)
Reference list for two authors: list both authors’ surnames and initials separated by commas, with an ampersand before the last author
Reference list for up to 20 authors: list all authors
Reference list for more than 20 authors: list the first 19 authors, an ellipsis, and the final author
Use the same author order as shown in the source
Capitalize only the first word of the title and subtitle, and proper nouns in reference list entries