You should use in-text citations whenever you directly quote from a source or whenever you paraphrase information you learned from a source.
Citing sources in either MLA Style or APA Style requires both a brief in-text citation and full details of each source on a final Works Cited (MLA) or References (APA) page. Every in-text citation points a reader to complete details of each source used.
In-text citations in MLA style require you to give author and specific page number(s) when available.
When citing direct quotations in APA Style, you will include author, year, and pages for the in-text citation at the end of the sentence. If you are paraphrasing though, you only include author and year for your in-text citation at the end of the sentence.
