| Number | Name | Date | Kind |
|---|---|---|---|
| 3523749 | MacLeod et al. | Aug 1970 | |
| 3765840 | Durr et al. | Oct 1973 | |
| 3783650 | Weber et al. | Jan 1974 | |
| 3784355 | Fielding | Jan 1974 | |
| 3806315 | Rosenbaum | Apr 1974 | |
| 3986824 | Waibel et al. | Oct 1976 | |
| 4080165 | Thompson | Mar 1978 | |
| 4111645 | Zurbuchen et al. | Sep 1978 | |
| 4218220 | Kappler et al. | Aug 1980 | |
| 4243391 | Puchta et al. | Jan 1981 | |
| 4575887 | Viramontes | Mar 1986 | |
| 4601845 | Namnath | Jul 1986 | |
| 4740213 | Ricci | Apr 1988 | |
| 5082468 | Hopkins | Jan 1992 |
| Entry |
|---|
| Encyclopedia of Chemical Technology, Third ed., vol. 8, 1979, pp. 280-350. |
| In ve Thorpe et al, 227 USPQ 964. |
| In ve Fitzgerald et al, 205 USPQ 594. |