1. Foreign body perforations of the gut;S., Ashby B.; G, Hunter-Craig I.;British Journal of Surgery,1967
2. A new device for endoscopic foreign body extraction;E., Frimberger; W, Kiihner;Endoscopy,1976
3. Endoscopic removal of sharp foreign objects using an oversleeve;S., Mee A.; P, Wright J.;South African Medical Journal; Foreign body in the oesophagus: Review of 2394 cases,1981
4. Fiberoptic removal of foreign bodies of the upper part cf the gastrointestinal tract;Alcola-Santaella, R.;Surgery, Gynecology and Obstetrics,1985
5. Management of ingested foreign bodies in childhood;Spitz, L.;British Medical Journal,1971