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MLA
Twain, Mark. Captain Stormfield’s Visit to Heaven. Harper & Brothers, 1909. Project Gutenberg. Sept. 1997. Hekman Library, Calvin College. 2 Jan 2003. <http://www.gutenberg.net/>.
APA -- ascii text
Belloc, B. R. (1863) Ballads and Songs. London: Bell and Daldy. Retrieved December 30, 2002, from Project Gutenberg