Mutakin, Firman, and Tumpal Sihaloho. “IKLIM USAHA INDUSTRI PENGOLAHAN BIJI KAKAO”. Buletin Ilmiah Litbang Perdagangan, vol. 1, no. 1, Jan. 2018, pp. 3-26, https://jurnal.kemendag.go.id/index.php/bilp/article/view/291.