Laacheb, D., and A. Khaldi. “Demographic Projections of the Active Population in Batna Province and Its Needs – Prospects for 2050 Using the Spectrum Program”. International Journal of Economic Perspectives, vol. 19, no. 9, Sept. 2025, pp. 86-101, http://ijeponline.org/index.php/journal/article/view/1153.