39c Follow conventions for capitalizing titles.

In titles and subtitles found in the text of a paper, all major words—nouns, pronouns, verbs, adjectives, and adverbs—should be capitalized. Minor words—articles, prepositions, and coordinating conjunctions—are not capitalized unless they are the first or last word of a title or subtitle. (In APA style, capitalize all words of four or more letters. See 53a.)

Titles of works are handled differently in the APA reference list. See “Preparing the list of references” in 53a.