1. Massera: Arch. ital. Chir.60, 20 (1941).
2. Sekiguchi: Arch. jap. Chir.9, 1151. Ref. Z.org. Chir.87, 58.
3. Sekiguchi: Arch. jap. Chir.10, 74. Ref. Z.org. Chir.63, 33.
4. Mazzacuva: Riv. Pat. sper.5, 343 (1930). Ref. Z. urol. Chir.32, 103.
5. Tomassini: Ann. ital. Chir.16, 471 (1937). Ref. Z.org. Chir.87, 58.