Whenever you include a paraphrase, summary, or direct quotation of another writer’s work in your paper, prepare your readers for it with an introduction called a signal phrase. A signal phrase usually names the author of the source and gives the publication date in parentheses.

You can use signal phrases to

When you write a signal phrase, choose a verb that is appropriate for the way you are supporting your argument. Are you arguing a point, making an observation, reporting a fact, drawing a conclusion, or refuting an argument? By choosing an appropriate verb, you can make your source’s role clear.

APA requires using the past tense or the present perfect tense in phrases that introduce quotations and other source material: Davis (2005) noted that or Davis (2005) has noted that, not Davis (2005) notes that. Use the present tense only for discussing the applications or effects of your own results (the data suggest) or knowledge that has clearly been established (researchers agree).

It is generally preferred in the social sciences to designate authors by their last name only, even on a first mention. If your paper refers to two authors with same last name, use initials as well.