Notable feminist sexologists include Anne Fausto-Sterling and Gayle Rubin. Other sexologists in the early gay rights movement included Ernst Burchard and Benedict Friedlaender. To date, the existence or extent of heterophobia is mostly unrecognized by sexologists. She is a member of the American College of Sexologists, and clinical sexologist. The term is used primarily by professional sexologists in the scientific literature. He received a doctorate (Ph.D.) in clinical sexology from the American Academy of Clinical Sexologists. Again, sexologists from many nations attended, colleagues from the United States forming the largest contingent.