Silalahi, Marina, Nisyawati, N., Walujo, Eko, AND Mustaqim, Wendy. " Ethnomedicine of Medicinal Plants By Batak Phakpak Subethnic in The Surung Mersada Village, Phakpak Bharat District, North Sumatera" Jurnal ILMU DASAR [Online], Volume 19 Number 2 (30 July 2018)