If it is an exact quote, it goes in quotation marks. If you are using your own words to summarize what the author said, you simply put the author's last name in parentheses at the end of the sentence with the page number. If it is a web page, you don't need the page number. This all depends on whether you are using APA or MLA. Our citation guide at https://libguides.daltonstate.edu/citation has examples of this situation for MLA and APA.