“Characteristic Levels of Total Petroleum Hydrocarbons in Soil, Sediment and Surface Water of an Oil Impacted Area in the Niger Delta” (2007) Biological Sciences - PJSIR, 50(4), pp. 247–250. Available at: https://www.biostaging.pjsir.org/index.php/biological-sciences/article/view/977 (Accessed: 21 March 2026).