Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4872526 | Sonic well logging tool longitudinal wave attenuator | David C. Hoyle | 1989-10-10 |
| 4862991 | Sonic well logging tool transmitter | David C. Hoyle, James J. Walulik | 1989-09-05 |