Soedomo, Sudarsono. “Internalizing Externalities through Payments for Environmental Services”. Jurnal Manajemen Hutan Tropika 18, no. 2 (December 18, 2012): 138-143. Accessed August 7, 2022. https://jagb.journal.ipb.ac.id/index.php/jmht/article/view/6059.