Number | Date | Country | Kind |
---|---|---|---|
3020668 | May 1980 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
3990840 | von der Eltz et al. | Nov 1976 | |
4299591 | Gregorian et al. | Nov 1981 |
Number | Date | Country |
---|---|---|
WO8000545 | Apr 1980 | WOX |
Entry |
---|
International Application No. PCT/US79/00759. |