by Abubakar, H. G., Abdulkareem, A. S., Jimoh, A., Agbajelola, O. D., Okafor, J. O., Afolabi, E. A.
Published in Energy sources. Part A, Recovery, utilization, and environmental effects (17.08.2016)

by E. J. Eterigho, T. S. Farrow, D. O. Agbajelola, S. E. Ejejigbe, A. P. Harvey
Published in Iranica journal of energy & environment (01.01.2016)