Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4838433 | Process for the separation of rock refuse and coal products | Gyula Kulcsar | 1989-06-13 |
| 4799738 | Mining method for working large-scale mineral deposits by the caving system | Karoly Barsi, Laszlo Kis-Tamas, Istvan Forisek, Laszlo Dorombozi, Otto Lukonits | 1989-01-24 |