1. Foreign bodies in the esophagus with respiratory symptoms complicating diagnosis;Naftzger;Report of Four Cases, Laryngoscope,1926
2. Respiratory difficulties in children due to foreign bodies in the oesophagus;Hupka;Cesk Otolaryngol,1962
3. Unsuspected foreign bodies in the young child's esophagus presenting with respiratory symptoms;Glass;Laryngoscope,1966
4. Bronchoesophagoscopy;Jackson,1950
5. Foreign body accidents involving the air and food passages in children;Friedberg;Otolaryngol Clin North Am,1970