Number | Date | Country | Kind |
---|---|---|---|
278360 | May 1977 | CAX |
Number | Name | Date | Kind |
---|---|---|---|
790238 | Wilcox | May 1905 | |
2716588 | Hall | Aug 1955 | |
2796342 | Schaufelberger et al. | Jun 1957 | |
2817583 | Schlecht et al. | Dec 1957 | |
3573896 | Hori et al. | Apr 1971 | |
3684489 | Emicke et al. | Aug 1972 | |
3744994 | Emicke et al. | Jul 1973 | |
3839013 | Turkdogan et al. | Oct 1974 | |
4067952 | Pittie et al. | Jan 1978 |
Entry |
---|
Shirts et al., Bureau of Mines Report of Investigations 7996, (1975). |