Number | Date | Country | Kind |
---|---|---|---|
3-39726 | Dec 1991 | JPX |
Number | Name | Date | Kind |
---|---|---|---|
4192065 | Tietjens | Mar 1980 | |
4240199 | Boiten et al. | Dec 1980 | |
4258470 | Boiten et al. | Mar 1981 | |
4347662 | Tietjens | Sep 1982 | |
4413410 | Otsuka et al. | Nov 1983 | |
4698908 | Bergsma et al. | Oct 1987 | |
4729169 | Asawa | Mar 1988 |