Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4934865 | Catchwater drain, excavating structure and method of construction | Laszlo Varkonyi, Csaba Asszonyi | 1990-06-19 |
| 4820080 | Process for the construction of a drain system | Laszlo Varkonyi, Csaba Asszonyi | 1989-04-11 |
| 4804293 | Flexible layer structure for protecting earthworks, bed walls and for delimiting embedding layers | Laszlo Varkonyi | 1989-02-14 |