Keho, Yaya. “Testing Wagner’s Law in the Presence of Structural Changes: New Evidence from Six African Countries (1960-2013)”. International Journal of Economics and Financial Issues 6, no. 1 (January 22, 2016): 1–6. Accessed December 23, 2024. https://econjournals.com./index.php/ijefi/article/view/1545.