1. The reproductive systems;Tortora,2000
2. Sexual arousal – its physiological roles in human reproduction;Levin;Annu Rev Sex Res,2005
3. Measurement of intra-vaginal and intra-uterine pressures during human coitus by radio-telemetry;Fox;J Reprod Fertil,1970
4. How do the spermatozoa enter the uterus?;Beck;Am J Obstet,1874
5. Development and inheritance;Tortora,2000