Ucler, G., and U. Bulut. “Re-Examination of the Convergence in Military Expenditures across NATO Countries: Do Different Approximations in Modelling Structural Breaks Matter?”. Applied Economics Journal, Vol. 28, no. 1, Dec. 2020, pp. 43-62, https://so01.tci-thaijo.org/index.php/AEJ/article/view/240922.