| Number | Name | Date | Kind |
|---|---|---|---|
| 3360877 | Estep | Jan 1968 | A |
| 3650058 | Wittcke et al. | Mar 1972 | A |
| 4612877 | Hayes et al. | Sep 1986 | A |
| 4920671 | Zatkos | May 1990 | A |
| 5473830 | Doble | Dec 1995 | A |
| 6055752 | Ritchey | May 2000 | A |
| Entry |
|---|
| NASCO Catalog, Mar. 2001, pp. 6, 8, 9, 10, 11. |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 29/141225 | May 2001 | US |
| Child | 10/251164 | US |