Tham khảo 69_(tư_thế_tình_dục)

  1. ↑ Rojiere, Jean (2001). The Little Book of Sex. Ulysses Press. ISBN 1-56975-305-9. 
  2. ↑ Julie Coleman, "Love, sex, and marriage: a historical thesaurus", Rodopi, 1999, ISBN 90-420-0433-9, p.214
  3. ↑ Aggrawal, Anil (2009). Forensic and Medico-legal Aspects of Sexual Crimes and Unusual Sexual Practices. Boca Raton: CRC Press. tr. 380. ISBN 1-4200-4308-0. 
  4. ↑ René James Hérail, Edwin A. Lovatt, "Dictionary of Modern Colloquial French", Routledge, 1990, ISBN 0-415-05893-7, p.484
  5. ↑ Rathus, Spencer A.; Nevid, Jeffrey S.; Fichner-Rathus, Lois; Herold, Edward S.; McKenzie, Sue Wicks (2005). Human sexuality in a world of diversity (ấn bản 2). New Jersey, USA: Pearson Education. tr. 221. ISBN 0-205-46013-5. 
  6. ↑ “Soixante-neuf definition and meaning | Collins English Dictionary”. www.collinsdictionary.com (bằng tiếng Anh). Collins English Dictionary. Truy cập ngày 8 tháng 7 năm 2018. 
  7. ↑ Legman 1969, p. 289