Onwualu-John, J. N., and O. P. Offodile. “Geochemical Assessment of Some Water Resources in Obio Akpor and Port Harcourt, Niger Delta Basin, Nigeria”. European Journal of Applied Sciences 10, no. 1 (February 4, 2022): 298–312. Accessed May 30, 2026. https://scholarpublishing.org/journals/index.php/EJAS/article/view/8193.