Sihotang, H. et al. 2012. MODEL KONSERVASI SUMBERDAYA AIR DANAU TOBA. Jurnal Pengelolaan Sumberdaya Alam dan Lingkungan (Journal of Natural Resources and Environmental Management). 2, 2 (Dec. 2012), 65. DOI:https://doi.org/10.29244/jpsl.2.2.65.