Here are some citation guidelines depending on which style guide the commission uses, as well as ways to get around a ban on citing ebooks. Also check to see if they have specific guidelines established for electronic sources. If they don't already, you may be setting the precedence!
It appears that it is unnecessary to cite specific page numbers when it comes to eBooks. If they absolutely require a page number, you may be able to use the "search inside" feature of Google Books and Amazon to find the printed page number. To me, saying "Chapter 1, section 2, paragraph 3" seems as exact as a specific page number anyway.
Hope that helps!