Electronic Sources you may wish to cite in your book or research paper may include ftp sites, telnet addresses, WWW and gopher pages, newsgroup and discussion list postings, and e-mail messages.
Be aware of the changing nature of electronic information - in citing these web resources, it is important that during the course of your research you make a note of the URL of the document you used to access information and of your access date.
Citation formats for Internet resources are still in development and no standard method for citing electronic sources of information has yet been agreed upon. See further resources for books and websites sites do however provide guidelines on electronic citation styles from a variety of sources.
Print sources
Print sources could include books, print journal articles, government publications, standards or conference proceedings.