This document discusses styles for citing sources, specifically the National Library of Medicine (NLM) style. It provides an example of how to format a citation for a journal article in NLM style, including author names, article title, journal title, date of publication, volume and issue numbers, and URL. The document also notes best practices for in-text citations, such as how often to cite and whether to use quotations. Readers are given homework to cite two articles in NLM style and submit them for feedback.