Cameron, Peter J. (2008) Introduction to algebra. 2nd ed. New York: Oxford University Press. Available at: http://ezproxy.library.qmul.ac.uk/login?url=http://www.vlebooks.com/vleweb/product/openreader?id=QMUL&isbn=9780191566226&uid=^u.
Ledermann, Walter and Weir, Alan J. (1996) Introduction to group theory. 2nd ed. Harlow: Longman.