| Number | Name | Date | Kind |
|---|---|---|---|
| D305764 | Westfield et al. | Jan 1990 | |
| D314382 | Scheid et al. | Feb 1991 | |
| D325579 | Bouhuys | Apr 1992 | |
| D327267 | Scheid et al. | Jun 1992 | |
| D343619 | Townsend et al. | Jan 1994 | |
| D348463 | Scheid et al. | Jul 1994 | |
| 3665475 | Gram | May 1972 | |
| 5197091 | Takagi et al. | Mar 1993 |