Assefa, M. ., L. . Fita, . U. . Galmessa, and A. . Bekuma. “The Status and Constraints of Primary Dairy Cooperatives in Selale Dairy Cooperative Union, Oromia Special Zone, Ethiopia”. Agricultural Advances, vol. 8, no. 11, Nov. 2019, pp. 481-94, http://sjournals.com/index.php/aa/article/view/107.