"The protection of computer software -- its technology and
applications Second edition," Derrick Grover (ed), The British
Computer Society Monographs in Informatics, Cambridge University
Press, New York, USA, 1989.
<http://www.amazon.com/exec/obidos/tg/detail/-/0521353351/qid=1059632472/sr=1-32/ref=sr_1_32/104-1160105-7007952?v=glance&s=books>