Issued Patents 1997
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5635653 | Ground water sampling device | Thomas M. Christy, Melvin P. Kejr | 1997-06-03 |
| 5612498 | Ground water sampling device | Thomas M. Christy, Melvin P. Kejr | 1997-03-18 |
| 5606139 | Soil sample probe with retaining ring for holding core-catching structure within the probe | Melvin P. Kejr, Thomas M. Christy | 1997-02-25 |