Number | Date | Country | Kind |
---|---|---|---|
2503966 | Jan 1975 | DEX |
Number | Name | Date | Kind |
---|---|---|---|
3280219 | Siebel et al. | Oct 1966 | |
3328377 | Cooper | Jun 1967 | |
3449471 | Weitzel et al. | Jun 1969 | |
3880951 | Ooya et al. | Apr 1975 | |
3886231 | Nield | May 1975 |
Number | Date | Country |
---|---|---|
1,238,207 | Apr 1967 | DEX |
2,238,967 | Feb 1974 | DEX |
Entry |
---|
Billmeyer, Textbook of Poly. Sci. (Interscience, 1962), pp. 346-347. |