Hutajulu, D. M., M. Nasir, and A. . “Analysis of the Leading Sector and the Effect of the Economic Growth: A Case Study in Pakpak Bharat Regency, Indonesia”. Studia Universitatis Vasile Goldiș Arad, Seria Științe Economice, Vol. 28, no. 3, Aug. 2018, pp. 37-49, https://publicatii.uvvg.ro/index.php/studiaeconomia/article/view/364.