| Number | Date | Country | Kind |
|---|---|---|---|
| 63-131914 | May 1988 | JPX | |
| 1-58278 | Mar 1989 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4264504 | Urakawa et al. | Apr 1981 | |
| 4374774 | Kasai et al. | Feb 1983 | |
| 4395558 | Kasai et al. | Jul 1983 | |
| 4791113 | Kunda et al. | Dec 1988 | |
| 4814445 | Vyas et al. | Mar 1989 | |
| 4880825 | Kasai et al. | Nov 1989 |
| Number | Date | Country |
|---|---|---|
| 0344990 | Dec 1989 | EPX |
| 122797 | Sep 1979 | JPX |
| 45322 | Mar 1980 | JPX |
| 118396 | Sep 1980 | JPX |
| Entry |
|---|
| The Merck Index, 10th Edition, 890-891 and 1097 (1983). |