Shaikh, S. Y., A. M. Malik, O. Khalid, and M. Mahnoor. “Comparison of Upper Pharyngeal Airway Space in Class II and Class III Malocclusion Cases”. Pakistan Orthodontic Journal, vol. 6, no. 1, July 2014, pp. 2-6, https://www.poj.org.pk/index.php/poj/article/view/88.