| Number | Name | Date | Kind |
|---|---|---|---|
| 3221464 | Miller | Dec 1965 | |
| 3568381 | Hale | Mar 1971 | |
| 3757478 | Pryor | Sep 1973 | |
| 3798849 | Biggs et al. | Apr 1974 | |
| 4137679 | Tully | Feb 1979 | |
| 4651479 | Kersavage | Mar 1987 |
| Entry |
|---|
| Cundy & Rollett Mathematical Models p. 129, p. 136 Plate 3 (d) 2nd Edition 1961. |