| Number | Date | Country | Kind |
|---|---|---|---|
| 1451/91 | May 1991 | CHX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 1850547 | Heintrich et al. | Mar 1932 | |
| 2070997 | Misslin et al. | Feb 1937 | |
| 2670346 | Bossard et al. | Feb 1954 | |
| 2714588 | Keller | Aug 1955 |
| Number | Date | Country |
|---|---|---|
| 0097289 | Jan 1984 | EPX |
| 0198102 | Dec 1906 | DE2 |
| 0747026 | Sep 1944 | DE2 |
| 294233 | Jan 1954 | CHX |
| 294234 | Jan 1954 | CHX |
| Entry |
|---|
| Derwent Abstract No. 89-237981 (1987). |
| Chem. Abst. 112:57805b (1990). |