Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4809779 | Arrangement for cleaning internal surface of casing strings | Oleg A. Ledyashov, Stanislav P. Goryainov, Mark L. Kiselman, Anatoly M. Laptev, Viktor I. Mishin | 1989-03-07 |