| Number | Date | Country | Kind |
|---|---|---|---|
| 3-298027 | Oct 1991 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5236719 | Meyers et al. | Aug 1993 |
| Number | Date | Country |
|---|---|---|
| 510977 | Jul 1980 | AUX |
| 0368451 | May 1990 | EPX |
| 0443788 | Aug 1991 | EPX |
| 0477089 | Mar 1992 | EPX |
| 2268473 | Nov 1975 | FRX |
| Entry |
|---|
| Patent Abstracts of Japan, CA112(18):160929u. |