“Studi Identifikasi Sebaran Ion Logam Pb, Cu, As Dan Cd Pada Air Dan Sedimen Di Perairan Bontang Kalimantan Timur Menggunakan Metode Kriging (Ordinary Kriging)”. GEOSAINS KUTAI BASIN 6, no. 1 (February 28, 2023): 34–39. Accessed November 23, 2025. https://jurnal.fmipa.unmul.ac.id/index.php/geofis/article/view/1001.