1. G. Jander, Lehrbuch für das anorg. chem. Praktikum [Textbook of Inorg. Chem. Practice], 5th ed., 1944, p. 188.
2. H. Funk. Darst. der Metalle im Laboratorium [Preparation of Metals in the Laboratory], Stuttgart, 1938, p. 66.
3. Private communication from Prof. G. Grube. See
4. Das duktile Chrom