N. Munyaneza, and Y. El Hachimi. 2019. “Utilization of Milk Urea Concentration to Study Nitrogen Use Efficiency in Haouz Dairy Herds of Central Morocco”. International Journal of Livestock Research 9 (5). India:32-39. https://ijlr.org/ojs_journal/index.php/ijlr/article/view/1249.