Number | Name | Date | Kind |
---|---|---|---|
3012539 | Warren | Dec 1961 | |
3230933 | Myers et al. | Jan 1966 | |
3311868 | Murto et al. | May 1974 | |
3388690 | Hostetler | Jan 1968 | |
3511215 | Myers | May 1970 | |
3911868 | Brembeck | Oct 1975 | |
4070990 | Swartzendruber | Jan 1978 | |
4317430 | Swartzendruber | Feb 1982 | |
4476811 | Swartzendruber | Oct 1984 | |
4834026 | Brembeck et al. | May 1989 |