Number | Date | Country | Kind |
---|---|---|---|
3424412 | Jul 1984 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
3340401 | Young | Sep 1967 | |
3621268 | Friedrich et al. | Nov 1971 | |
3737668 | Ellis et al. | Jun 1973 | |
3860754 | Johnson et al. | Jan 1975 | |
4049964 | Wuchinich et al. | Sep 1977 | |
4514817 | Pepper et al. | Apr 1985 |
Number | Date | Country |
---|---|---|
3306941 | Aug 1984 | DEX |
8303691 | Oct 1983 | HUX |
Entry |
---|
T. F. Cummings--"Transparent Keyless Keyboard for Variable Terminal Applications"--IBM Technical Disclosure Bulletin--vol. 20, No. 4--Sep./77--pp. 1609-1611. |