Number | Date | Country | Kind |
---|---|---|---|
2700293 | Jan 1977 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
3766083 | Langstroth et al. | Oct 1973 | |
3954740 | Fringeli | May 1976 | |
4025507 | Fleck et al. | May 1977 | |
4072911 | Hartig et al. | Feb 1978 |
Number | Date | Country |
---|---|---|
7607198 | Jan 1977 | NLX |
Entry |
---|
Majewski et al., Optics Communications, Aug. 1976, vol. 18, No. 3, pp. 255-259. |