Hasan, I., R. Abdullah, J. Saputra, Z. Putra, y D. K. S. Chalirafi. «The Internal Market of Dairy Cooperatives: Chances and Challenges of Global-Market». Opción, Vol. 35, junio de 2019, pp. 1833-64, https://produccioncientificaluz.org/index.php/opcion/article/view/24105.