Berek, F., A. Dethan, and P. Tahuk. “The Effect of Long Shelf Life of Duroc Pig Male Semen Diluted Using Tris-Egg Yolk-Young Coconut Water on The Value of Viability, Abnormality and PH”. Journal of Tropical Animal Science and Technology, Vol. 3, no. 2, Aug. 2021, pp. 108 -20, doi:10.32938/jtast.v3i2.1201.