| S. No. | Patent identifier |
|---|---|
| 1 | US4757124A |
| 2 | US4758639A |
| 3 | US5858571A |
| 4 | EP0172427B1 |
| 5 | US10195216B1 |
| 6 | CN103435584A |
| 7 | EP0872903A1 |
| 8 | US6277519B1 |
| 9 | EP0172427A2 |
| 10 | US5070088A |
| 11 | US20100009927A1 |
| 12 | CN104428036A |
| 13 | US5968225A |
| 14 | EP0843371A1 |
| 15 | EP0872903B1 |
| 16 | EP0843371B1 |
