1. Novak’s Textbook of Gynecology;Novak,1961
2. Fluidity of Menstrual Blood; A Proteolytic Effect;Huggins;Am. J. Obstet. Gynec.,1943
3. Vaginal Tampons and Their Relationship to the Cervix Uteri as Determined by Roentgenography;Kovar;Obstet. Gynec.,1959
4. Textbook of Gynecology;Curtis,1950
5. Tampons in Menstrual Hygiene;Wheatley;JAMA,1965