Obiefuna, J. N., E. O. Inah, E. A. Etim, I. I. Etuk, and R. Effiong. “The Contributions and Challenges of Sustainable Tourism Development in Calabar, Cross River State, Nigeria”. Journal of Public Administration, Policy and Governance Research, vol. 3, no. 3, July 2025, pp. 190-7, https://jpapgr.com/index.php/research/article/view/234.