Thapa, V. B., A. Shrestha, P. Sherchan, P. Poudel, and L. Joshi. “Twin Block Appliance: Effect on Pharyngeal Airway”. Journal of Kathmandu Medical College, vol. 7, no. 4, Dec. 2018, pp. 147-52, https://jkmc.com.np/ojs3/index.php/journal/article/view/468.