| Number | Date | Country | Kind |
|---|---|---|---|
| 2200024 | Mar 1997 | CAX |
| Number | Name | Date | Kind |
|---|---|---|---|
| RE35291 | Lafond | Jul 1996 | |
| 4756789 | Kolff | Jul 1988 | |
| 4831799 | Glover et al. | May 1989 | |
| 5013377 | Lafond | May 1991 | |
| 5472558 | Lafond | Dec 1995 | |
| 5865942 | Sinclair | Feb 1999 |
| Entry |
|---|
| Edgetech Newsletter vol. 1 No. 2 Winter 1990, 2 pages. |
| Edgetech Newsletter vol. 2 No. 1 Fall 1991, 2 pages. |