Number | Name | Date | Kind |
---|---|---|---|
1388086 | Ashcroft | Aug 1921 | |
3894927 | Kane et al. | Jul 1975 | |
4024221 | Becker et al. | May 1977 | |
4029733 | Faugeras et al. | Jun 1977 | |
4039647 | Wohleber et al. | Aug 1977 | |
4039648 | Haupin et al. | Aug 1977 |
Number | Date | Country |
---|---|---|
2295129 | Jul 1976 | FRX |
Entry |
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Beck et al. (1), "APC Publication Ser. No. 292742", published 7/13/43. |
Beck et al. (2), "APC Publication Ser. No. 393258", published 7/13/43. |
Spedding et al., "The Rare Earths", John Wiley & Sons, N.Y. 1961. |