^Lisa Downing, "Eros and Thanatos in European and American Sexology" in Kate Fisher, Sarah Toulalan (eds.) Bodies, Sex and Desire from the Renaissance to the Present, Macmillan, 2011, ISBN 0230283683
Rudy Flora, "How to work with sex offenders: a handbook for criminal justice, human service, and mental health professionals", Routledge, 2001, ISBN 0-7890-1499-8, p. 90