Asmara, Alla, Yeti Lis Purnamadewi, and Deni Lubis. “KERAGAAN PRODUKSI SUSU DAN EFISIENSI USAHA PETERNAKAN SAPI PERAH RAKYAT DI INDONESIA”. Jurnal Manajemen & Agribisnis 13, no. 1 (March 6, 2016): 14. Accessed October 29, 2020. https://journal.ipb.ac.id/index.php/jmagr/article/view/12255.