Chukwuma, O. M., E. E. Edith, M. D. Alfa, Y. A. Babadoko, W. O. Ebhohimen, and C. C. Uchenna. “The Solid Mineral Sector and Economic Diversification in Nigeria”. Lapai Journal of Economics, vol. 2, no. 2, Dec. 2018, pp. 123-42, doi:10.2022/lje.v2i2.12.