Final answer:
In citations, if an article has multiple authors, list the first author's last name followed by 'et al.' in the parentheses for works with more than two authors.
Step-by-step explanation:
When you are citing an article that has multiple authors, you should put the first author's last name in the parentheses followed by 'et al.' to represent additional authors. This applies if the work has more than two authors. For example: (Pronkowski et al. 9).
However, if you are citing a work with only two authors, include both authors' names, such as (Kristof & WuDunn). It is also important to note that when you are citing more than twenty authors, you list the first nineteen and then use an ellipsis before the final author's name.
When citing an article with multiple authors in APA style, you should include the last name of the first author followed by 'et al.' For example, if the article is written by Smith, Johnson, and Brown, you would cite it as (Smith et al.).