If there is more than one study by the author on that point, list the year of the other studies.
Last name of the author, First name of the author. “Source’s Title.” Container’s Title , roles and names of any other individuals who helped contribute to the source, the version of the source, any numbers associated with the source, the name of the publisher, the date the source was published, the location where individuals can find the source themselves (usually a URL or page range).
When an electronic source lacks page numbers, you should try to include information that will help readers find the passage being cited. When an electronic document has numbered paragraphs, use the ¶ symbol, or the abbreviation "para." followed by the paragraph number (Hall, 2001, ¶ 5) or (Hall, 2001, para. 5). If the paragraphs are not numbered and the document includes headings, provide the appropriate heading and specify the paragraph under that heading. Note that in some electronic sources, like Web pages, people can use the Find function in their browser to locate any passages you cite. According to Smith (1997), ... (Mind over Matter section, para. 6). Note: Never use the page numbers of Web pages you print out; different computers print Web pages with different pagination.