“Heavy Metal Content in Sediment and Hora Shell (Cerithidea Obtusa) in Panipahan Waters, Rokan Hilir, Riau”. Jurnal Natur Indonesia 19, no. 2 (October 22, 2021): 29–36. Accessed May 15, 2025. https://hirameki.ejournal.unri.ac.id/index.php/natur/article/view/1668.