| Number | Date | Country | Kind |
|---|---|---|---|
| 101 09 321 | Feb 2001 | DE |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4270903 | Nash | Jun 1981 | A |
| 4830615 | Feinman et al. | May 1989 | A |
| 5063118 | Goetz | Nov 1991 | A |
| 5476381 | Dragan | Dec 1995 | A |
| 5836810 | Asum | Nov 1998 | A |
| Number | Date | Country |
|---|---|---|
| 117888 | Dec 1926 | CH |
| 0 354 870 | Jul 1989 | EP |
| 2059266 | Apr 1981 | GB |
| Entry |
|---|
| English translation of HOPF, Paul 117888 patent. |