Quan A, Leung SW, Lao TT, Man RY (December 2003). "5-hydroxytryptamine and thromboxane A2 as physiologic mediators of human umbilical artery closure". J. Soc. Gynecol. Investig. 10 (8): 490–5. doi:10.1016/S1071-5576(03)00149-7. PMID14662162.
Quan A, Leung SW, Lao TT, Man RY (December 2003). "5-hydroxytryptamine and thromboxane A2 as physiologic mediators of human umbilical artery closure". J. Soc. Gynecol. Investig. 10 (8): 490–5. doi:10.1016/S1071-5576(03)00149-7. PMID14662162.