Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4458947 | Mining method | Wynand J. van der Westhuizen | 1984-07-10 |
| 4432422 | Borehole guide and method of boring interpenetrating holes | Wynand J. van der Westhuizen | 1984-02-21 |