M.S, S., N. Lyndon, R. A. Che Rose, S. Selvadurai, and R. Ramly. “Peranan Koperasi Dalam Meningkatkan Pendapatan Pekebun Kecil: Kajian Kes Koperasi Penanaman Sawit Mampan (KPSM): The Role of Cooperatives in Increasing Smallholder’s Income: Case Study on Sustainable Palm Oil Cooperative (KPSM)”. GEOGRAFI, vol. 5, no. 3, Dec. 2017, pp. 64-71, https://ojs.upsi.edu.my/index.php/GEOG/article/view/2069.