American Psychological Association (2008). Answers to Your Questions: For a Better Understanding of Sexual Orientation and Homosexuality. Washington, DC: American Psychological Association. Available online: http://www.apa.org/topics/sexuality/orientation.aspx.
APA Committee on Lesbian, Gay, Bisexual, and Transgender Concerns (2011). Answers to Your Questions About Transgender Individuals and Gender Identity. Washington, DC: American Psychological Association. Available online: http://www.apa.org/topics/sexuality/transgender.aspx.
Biggs WS (2011). Medical human sexuality. In RE Rakel, DP Rakel, eds., Textbook of Family Medicine, 8th ed., pp. 1000–1012. Philadelphia: Saunders.
Cromer B, et al. (2011). Adolescent development. In RM Kliegman et al., eds., Nelson Textbook of Pediatrics, 19th ed., pp. 649–659. Philadelphia: Saunders.
Hillman JB, Spigarelli MG (2009). Sexuality: Its development and direction. In WB Carey et al., eds., Developmental-Behavioral Pediatrics, 4th ed., pp. 415–425. Philadelphia: Saunders Elsevier.
Sadock VA (2009). Normal human sexuality and sexual and gender identity disorders. In BJ Sadock et al., eds., Kaplan and Sadock’s Comprehensive Textbook of Psychiatry, 9th ed., vol. 1, pp. 2027–2060. Philadelphia: Lippincott Williams and Wilkins.
Sass AE, Kaplan DW (2011). Adolescence. In WW Hay et al., eds., Current Diagnosis and Treatment: Pediatrics, 20th ed., pp. 104–144. New York: McGraw-Hill.
Zucker KJ (2011). Gender identity and sexual behavior. In CD Rudolph et al., eds., Rudolph's Pediatrics, 22nd ed., pp. 346–348. New York: McGraw-Hill.