| Number | Name | Date | Kind |
|---|---|---|---|
| D324709 | Lehtonen | Mar 1992 | |
| D337799 | Cutter et al. | Jul 1993 | |
| 4846461 | Robards, Jr. et al. | Jul 1989 | |
| 4880224 | Jonas et al. | Nov 1989 | |
| 4974832 | Dalebout | Dec 1990 | |
| 5013033 | Watterson et al. | May 1991 | |
| 5072929 | Peterson et al. | Dec 1991 | |
| 5076573 | Lo | Dec 1991 |