SUMARNO, E. PELESTARIAN DAN PERLINDUNGAN TEMBAKAU DELI Sebuah Perspektif Historis. Jurnal Online Pertanian Tropik, [S. l.], v. 3, n. 3, p. 187–205, 2019. DOI: 10.32734/jopt.v3i3.2976. Disponível em: https://idjpcr.usu.ac.id/jpt/article/view/2976. Acesso em: 5 aug. 2025.