YUSUF, M.; HUTABARAT, S.; HADI, S. . Analysis of The Implementation of ISPO Certification on Smallholder Oil Palm Plantation in Beringin Jaya Cooperation Koto Ringin Village Mempura Sub-District Siak District . Journal of Agribusiness and Community Empowerment (JACE), [S. l.], v. 4, n. 2, p. 121–133, 2021. DOI: 10.32530/jace.v4i2.247. Disponível em: http://jurnalpolitanipyk.ac.id/index.php/JACE/article/view/247. Acesso em: 3 aug. 2025.