Number | Name | Date | Kind |
---|---|---|---|
2099102 | Brown et al. | Nov 1937 | |
3240444 | Gentile | Mar 1966 | |
3940086 | Stoquelet | Feb 1976 | |
4880182 | Gelfman | Nov 1989 | |
4901939 | Obst et al. | Feb 1990 |
Number | Date | Country |
---|---|---|
954245 | Jan 1964 | GBX |
Entry |
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Porta Systems Corp. publication PRTA 201-139-410 Issue 1, Jul. 1991, pp. 1-3. |