Onojake, M. C., Sikoki, F. D., Omokheyeke, O., & Akpiri, R. U. (2017). Surface water characteristics and trace metals level of the Bonny/New Calabar River Estuary, Niger Delta, Nigeria. Applied Water Science, 7(2), 951-959. https://doi.org/10.1007/s13201-015-0306-y