Chicago Manual of Style You are viewing the free, open access version of The Nature of Writing. For all premium membership features (including quizzes, additional lessons, course progress tracking, and more), please register or log in. Introduction Intro to CMS Notes Footnotes and Endnotes The Bibliography Formatting the BibliographyParts of a CitationDOIs and URLs Types of Sources BooksPeriodicalsOnline SourcesNewspapersAudiovisual SourcesManuscript CollectionsInterviews and Messages