F. O. Nwosu, F. A. Adekola, and A. O. Salami, trans. “Adsorption of 4-Nitrophenol Using Pilli Nut Shell Active Carbon”. Pakistan Journal of Analytical & Environmental Chemistry 18, no. 1 (June 23, 2017): 69 – 83. Accessed November 5, 2025. https://pjaec.pk/index.php/pjaec/article/view/225.