[1]
M Sianturi, N. et al. 2018. Assessment of Environmental Management in Lake Toba, Samosir Regency, North Sumatera Province, Indonesia. International Journal of Engineering & Technology. 7, 3.14 (Jul. 2018), 337–343. DOI:https://doi.org/10.14419/ijet.v7i3.14.18815.