“Effects of Estrogen Treatment on Sexual Behavior in Male-to-Female Transsexuals: Experimental and Clinical Observations”:
http://www.susans.org/reference/estroeff.html
“Mortality and morbidity in transsexual subjects treated with cross-sex hormones”:
http://www.ncbi.nlm.nih.gov/pubmed/9373456
“A long-term follow-up study of mortality in transsexuals receiving treatment with cross-sex hormones”:
http://www.eje-online.org/content/164/4/635.full.pdf
Hormone Effects (video):
http://www.youtube.com/watch?v=KNY10PKc6TI