Number | Date | Country | Kind |
---|---|---|---|
2909231 | Sep 1979 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
3397767 | Hobbs | Aug 1968 | |
3904017 | Frechette | Sep 1975 | |
3964595 | Edstrom | Jun 1976 |
Number | Date | Country |
---|---|---|
2820266 | Nov 1978 | DEX |
Entry |
---|
IBM Technical Disclosure Bulletin, vol. 22, No. 6, Nov. 1979, Schaefer, "Two-Color Cartridge Ribbon System with Correction," pp. 2327-2329. |