There is no page number in the ebook, how can I reference a Safari ebook in a paper? 

This article provides a guideline to help you format a citation from Safari Books Online content.

There are many writing style formats for citation, and they differ in their citation methods. This basic information will assist you in citing Safari Books Online content in your research paper.

Most writing styles require author, title, and publication date, all of which are available on the catalog page:

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Citing the location of the chapter within a book can be done by use of the URL button found at the top of the Content Reader:

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This is the page of the book within Safari Books Online, and it may not always correspond to the page number of the original hard copy book.   

Since you are citing the online version you should cite the page number and URL as they appear in Safari Books Online. Online versions of technical documents frequently have different page numbers than print versions. The purpose of the citation is to point users to the correct online page, not duplicate the numbering of the original printed document.

Additional information on citing online sources can be found at http://www.mla.org/style/style_faq/mlastyle_cite_an_ebook .