Number | Date | Country | Kind |
---|---|---|---|
2902870 | Jan 1979 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
2833885 | Wells et al. | May 1958 | |
3634793 | Sauer | Jan 1972 | |
4087667 | Heider et al. | May 1978 |
Number | Date | Country |
---|---|---|
1213917 | Oct 1966 | DEX |
2454967 | Dec 1976 | DEX |
Entry |
---|
"Relais Lexikon", by H. Sauer, 1975, p. 12. |
"Publication Elektronik", vol. 60, Issue 24 of Dec. 27, 1978, p. 43. |