Sihotang, Hotland, M. Yanuar J. Purwanto, Widiatmaka Widiatmaka, and Sambas Basuni. 2012. “MODEL KONSERVASI SUMBERDAYA AIR DANAU TOBA”. Jurnal Pengelolaan Sumberdaya Alam Dan Lingkungan (Journal of Natural Resources and Environmental Management) 2 (2): 65. https://doi.org/10.29244/jpsl.2.2.65.