共 24 条
- [1] ANDERSON JL, 1956, Patent No. 2729680
- [2] BARTON JED, 1972, Patent No. 1445087
- [3] CHRISTENSEN BG, 1973, Patent No. 2318829
- [4] DUTRA AG, 1977, Patent No. 2751630
- [5] DUTRA AG, 1976, Patent No. 4067719
- [6] DUTRA AG, 1976, Patent No. 130857
- [7] DUTRA AG, 1977, Patent No. 12910331
- [8] DUTRA AG, 1978, Patent No. 4083898
- [10] ISSLEIB K, 1979, Patent No. 211108