Olujobi, O. J., and O. A. Oyewunmi. “Annulment of Oil Licences in Nigeria’s Upstream Petroleum Sector: A Legal Critique of the Costs and Benefits”. International Journal of Energy Economics and Policy, vol. 7, no. 3, July 2017, pp. 364-9, https://econjournals.com/index.php/ijeep/article/view/4576.