Manullang, Helentina Mariance, and Khairul Khairul. “Growth Pattern Study of Slender Walking Catfish (Clarias Nieuhofii) As Environmental Biology Indicator”. Jurnal Mangifera Edu 5, no. 1 (July 31, 2020): 1-7. Accessed October 24, 2020. https://jurnal.biounwir.ac.id/index.php/mangiferaedu/article/view/97.