Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4821246 | Electromagnetic vibrator for seismic and civil-engineering applications | Anne R. Ritsema, Rudolf Unger | 1989-04-11 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4821246 | Electromagnetic vibrator for seismic and civil-engineering applications | Anne R. Ritsema, Rudolf Unger | 1989-04-11 |