1. Pyriform sinus fistula;Miyauchi;Arch Surg,1981
2. Acute suppurative thyroiditis and pyriform sinus fistula;Nishi;Jpn J Pediatr Surg,1985
3. Pyriform sinus fistula: Surgical consideration;Muraji;Jpn J Pediatr Surg,1989
4. A case of pyriform sinus fistula;Ohno;J Jpn Soc Pediatr Surg,1989
5. The endoscopic and surgical management of pyriform sinus fistula;Makino;J Pediatr Surg,1986