1. W. Köster and E. Wagner,Z. Metallkd., 29,230–232(1937).
2. W. Köster,Z. Metallkd., 29,232–234(1937).
3. U. Hashimoto,Nippon Kinzoku Gakkai-Si 2, 66–77 (1938);J. Jpn. Inst. Met., 2,348-359 (1938).
4. W. Köster and K. Lang,Z. Metallkd., 30,350–352 (1938).
5. P. Pietrokowsky and P. Duwez,Trans. AIME, 188, 1283–1284 (1950).