R. S. Akande, O. A. Hammed, A. M. Shitu, and Y. T. Yusuf, “Regulatory Efficiency and Informal Economy: Impact on Tax Revenue in West Africa”, AJMBR, vol. 18, no. 1, pp. 199–217, Mar. 2025, doi: 10.62154/ajmbr.2025.018.010608.