Asif, Muhammad, et al. “FOREIGN BODY INHALATION - SITE OF IMPACTION AND EFFICACY OF RIGID BRONCHOSCOPY”. Journal of Ayub Medical College Abbottabad, vol. 19, no. 2, June 2007, pp. 46-48, https://jamc.ayubmed.edu.pk/index.php/jamc/article/view/5011.