Rosenta Purba, Ika, and Nurhayati Nurhayati. “Water Quality Of Lake Toba By Space And Time Based On Environmental Physics, Chemical Factors And Community Phytoplankton”. Eduvest - Journal of Universal Studies 2, no. 11 (November 20, 2022): 2379–2396. Accessed July 5, 2025. http://www.eduvest.greenvest.co.id.submitjurnal.id/index.php/edv/article/view/609.