RT Journal Article SR Electronic T1 Biological aspects of homosexuality. JF Journal of Medical Ethics JO J Med Ethics FD BMJ Publishing Group Ltd and Institute of Medical Ethics SP 133 OP 138 DO 10.1136/jme.6.3.133 VO 6 IS 3 A1 M MacCulloch YR 1980 UL http://jme.bmj.com/content/6/3/133.abstract AB