| Number | Name | Date | Kind |
|---|---|---|---|
| D326715 | Schmidt | Jun 1992 | |
| 4685464 | Goldberger et al. | Aug 1987 | |
| 4825879 | Tan et al. | May 1989 | |
| 4867165 | Noller et al. | Sep 1989 | |
| 4883055 | Merrick | Nov 1989 | |
| 4913150 | Cheung et al. | Apr 1990 | |
| 4964408 | Hink et al. | Oct 1990 | |
| 5035243 | Muz | Jul 1991 | |
| 5080098 | Willett et al. | Jan 1992 | |
| 5249576 | Goldberger et al. | Oct 1993 |