The MLA Style Manual and Guide to Scholarly Publishing, 3rd Edition (2008), provides guidelines for citing printed material reproduced on the web in section 6.7.2.c (pp. 216-17). It states that such sources should be cited with the bibliographical information for the printed edition first (including page numbers, if not citing the whole volume), followed by the online source, and concluding with the date of access and the URL. For example:
Spenser, Edmund. The Faerie Queene. London, 1590. N. pag. Early English Books Online: Text Creation Partnership. U of Michigan Library. Web. 5 November 2009. http://name.umdl.umich.edu/A12777.0001.001/.
The Chicago Manual of Style, 16th Edition (2010), discusses printed books published online in sections 14.167-69, 14.271) (pp. 727-28, 763-64). They suggest such sources should be cited as follows:
Spenser, Edmund. The Faerie Queene. London, 1590. N. pag. Early English Books Online: Text Creation Partnership. Accessed November 5, 2009. http://name.umdl.umich.edu/A12777.0001.001/.
In footnotes and endnotes, information on publication location and date is placed in parentheses, and commas are substituted for periods (except at the conclusion of the citation).
The URL cited above is taken from the version of the EEBO-TCP texts hosted by the University of Michigan Library. If you accessed the text through some other interface (e.g., ProQuest’s EEBO), you would cite that URL instead.