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Math 317 Statistics and Research Methods Laboratory (Pennell): Getting Started
Several online-only journals (e.g., PLoS ONE) publish articles that have article numbers rather than unique page ranges. That is, instead of the first article in the issue starting on page 1, the second on page 20, the third on page 47, and so on, every article starts on page 1.
Two or More Works by the Same Author in the Same Year: If you have two sources by the same author in the same year, use lower-case letters (a, b, c) with the year to order the entries in the reference list. Use the lower-case letters with the year in the in-text citation.
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 abbreviation "para." followed by the paragraph number (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.... According to Smith (1997), ... (Mind over Matter section, para. 6).