If a source has multiple authors, follow these guidelines.
Two authors in a parenthetical citation: Use an ampersand (&) between the two last names.
Two authors in the narrative: Use and between the two last names.
Three or more authors: Only cite the first author, followed by et al.
If directly quoting, include the author, year of publication, and page number for the reference. Introduce the quote with a phrase like according to or state the author's last name.
If you do not name the author in the sentence, list it with the date and page numbers after the quotation.