Correlation between vaginal cytology and serum progesterone in Sumatran rhinoceros (Dicerorhinus sumatrensis) - Yusoff, Rosnina; Choong, Siew Shean; Zainuddin, Zainal Zahari; Haron, Abd. Wahid; Mohamad, Aidi; Yap, Keng Chee (Research Management Centre, 2002)