| Number | Name | Date | Kind |
|---|---|---|---|
| 2846330 | Berthold et al. | Aug 1958 | |
| 3931079 | Wise et al. | Jan 1976 | |
| 4208213 | Muller et al. | Jun 1980 | |
| 4363893 | Hersh | Dec 1982 | |
| 4497919 | Varga et al. | Feb 1985 | |
| 4804413 | Lee | Feb 1989 | |
| 5180638 | Teekman | Jan 1993 |
| Number | Date | Country |
|---|---|---|
| 588682 | Dec 1959 | CAX |
| 220322 | Mar 1985 | DEX |
| 3930413 | Jan 1991 | DEX |
| 1121278 | Oct 1984 | SUX |
| 1060620 | Mar 1967 | GBX |
| 2227753 | Aug 1990 | GBX |
| Entry |
|---|
| Chemical Abstract No. 90:88916, which is an abstract of Czech . Patent No. 174,593 (Oct. 1978). |