Akbaş, Aykut, Mehmet Sari, Zafer Usta, and Mustafa Saatci. “A Field Study on Fertility Traits of Holstein Heifer and Cows Artificially Inseminated With Sexed Belgian Blue Sperm and Growth Characteristics of Crossbreed Belgian Blue × Holstein (F1) Male Calves”. Proceedings of the Bulgarian Academy of Sciences 75, no. 7 (July 29, 2022): 1072–1081. Accessed December 5, 2022. http://www.proceedings.bas.bg/index.php/cr/article/view/125.