“Avoiding Heterosexual Bias in Language”. American Psychological Association. http://www.apa.org/pi/lgbt/resources/language.aspx. "The term sexual orientation is preferred to sexual preference for psychological writing and refers to sexual and affectional relationships of lesbian, gay, bisexual, and heterosexual people. The word preference suggests a degree of voluntary choice that is not necessarily reported by lesbians and gay men and that has not been demonstrated in psychological research."
