| Number | Name | Date | Kind |
|---|---|---|---|
| D226688 | Thornton | Apr 1973 | |
| D316754 | Lau | May 1991 | |
| D376430 | Humphrey et al. | Dec 1996 | |
| 3145867 | Roberts et al. | Aug 1964 | |
| 4570808 | Campbell et al. | Feb 1986 | |
| 4676387 | Stephenson et al. | Jun 1987 | |
| 4813556 | Lawrence | Mar 1989 | |
| 4832213 | Sharon et al. | May 1989 | |
| 4867325 | Dransfield | Sep 1989 |