Rehman, A.- ur-., O. F. . Zain, and F. . Arshad. “Threat to International Aviation Industry: Liquid Explosive Detection Systems and Liquid Aerosols & Gels”. Pakistan Journal of Social Sciences, vol. 41, no. 1, Mar. 2021, pp. 33-47, http://pjss.bzu.edu.pk/index.php/pjss/article/view/976.