When you are required to use the Oxford referencing style, the citation of an electronic book should include sufficient information to enable the reader to access or retrieve it. In that sense, references should have at least the following elements:
Surname, First name, Title [online text], (place of publication: publisher, year), in Library database, accessed DD Month YYYY
Here, you have an example of how an e-book should be cited in the bibliography or reference list:
Kelsall, Robert, Hamley, Ian and Geoghegan, Mark, Nanoscale Science and Technology [online text], (Chichester: John Wiley & Sons Ltd., 2005), in Google books, accessed 16 February 2013
If you use a footnote, the reference will look very similar, except for the order of the first two elements and the use of lower case letters instead of all capitals. In the example above, the footnote will look like:
Robert Kelsall, Ian Hamley and Mark Geoghegan, Nanoscale Science and Technology [online text], (Chichester: John Wiley & Sons Ltd., 2005), in Google books, accessed 16 February 2013
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