Ross, Michael W.; Essien, E. James; Williams, Mark L.; Fernandez-Esquer, Maria Eugenia. (2003). "Concordance Between Sexual Behavior and Sexual Identity in Street Outreach Samples of Four Racial/Ethnic Groups". Sexually Transmitted Diseases. American Sexually Transmitted Diseases Association. 30 (2): 110–113. doi:10.1097/00007435-200302000-00003. PMID12567166.
Ross, Michael W.; Essien, E. James; Williams, Mark L.; Fernandez-Esquer, Maria Eugenia. (2003). "Concordance Between Sexual Behavior and Sexual Identity in Street Outreach Samples of Four Racial/Ethnic Groups". Sexually Transmitted Diseases. American Sexually Transmitted Diseases Association. 30 (2): 110–113. doi:10.1097/00007435-200302000-00003. PMID12567166.