Number | Date | Country | Kind |
---|---|---|---|
3539290 | Nov 1985 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
1876640 | Dobson | Sep 1932 | |
2126326 | Helmond | Aug 1938 | |
4215762 | Cunningham | Aug 1980 |
Number | Date | Country |
---|---|---|
842583 | Jul 1960 | GBX |
Entry |
---|
IBM Technical Disclosure Bulletin, vol. 26, No. 1, Jun. 1983. |