The Contribution of the Community Forest Program to the Income of the Lumban Lansang Forest Farmer Group, Siantar Utara Village, Parmaksian District, Toba Samosir Regency. Jurnal Online Pertanian Tropik, [S. l.], v. 9, n. 3, p. 201–206, 2023. DOI: 10.32734/jopt.v9i3.9234. Disponível em: https://idjpcr.usu.ac.id/jpt/article/view/9234. Acesso em: 4 feb. 2026.