| Number | Name | Date | Kind |
|---|---|---|---|
| D. 158972 | Jonassen | Jun 1950 | |
| D. 204022 | Ramp | Mar 1966 | |
| D. 210697 | Ramp | Apr 1968 | |
| 2714717 | Allman | Aug 1955 | |
| 5026150 | Weber | Jun 1991 | |
| 5376977 | Liu | Dec 1994 | |
| 5614963 | Parker | Mar 1997 | |
| 6089708 | Ku | Jul 2000 |
| Entry |
|---|
| New York Times, p. A3, Mar. 20, 1997. |