Samsuri, Affifuddin, Y. . and Faisal Ridho (2022) “Study of policy determination to create a healthy watershed: A case study of Lepan watershed in Langkat district, North Sumatera, Indonesia”, Journal of Sylva Indonesiana, 5(01), pp. 33–46. doi: 10.32734/jsi.v5i01.6222.