1. A looped catheter in the treatment of ureteral calculi;Balkus;Journal of Urology,1943
2. Komplikationen nach instrumentellen Eingriffen am Ureter;Baumgartner;Helvetica Chirurgica Acta,1975
3. Loop catheter delivery of ureteral calculi;Bowers;Journal of Urology,1973
4. Removal of ureteral calculus by a new catheter type extractor;Davis;Journal of Urology,1954
5. The treatment of patients with ureteral calculi;Dodson;Journal of Urology,1957