HARAHAP, Anwar Sadat, 		MULYONO, Hardi, 		HASIBUAN, Ahmad laut, AND 		SIREGAR, Taufik.
" South Batak Tradition for the Settlement of Environmental Disputes: A Tumbaga Holing Letter Model" <em>Journal of Environmental Management and Tourism</em> [Online], Volume 12 Number 7 (1 December 2021)