1. Sigman M, Jarow JP: Male Infertility. In Campbell’s Urology, edn 8. Edited by Walsh P, Retik AB, Vaughan ED Jr, et al. St. Louis: Saunders; 2002:1475–1531.
2. World Health Organization: WHO Laboratory Manual for the Examination of Human Semen and Sperm-cervical Mucus Interation. Cambridge: World Health Organization; 1999.
3. Brooks J: Anatomy of the lower urinary tract and male genitalia. In Campbell’s Urology, edn 8. Edited by Walsh P, Retik AB, Vaughan ED Jr. St. Louis: Saunders; 2002:63–65.
4. Turner T: The epididymis and accessory sex organs. In Infertility in the Male, edn 3. Edited by Lipschultz L, Howards S. St. Louis: Mosby; 1997:147–150.
5. Wolff H: The biological significance of white blood cells in semen. Fertil Steril 1995, 63:1143–1157.