1. Comp. Rend., 1929,188, 1151.
2. Ann. der Phys., 1935,23, 425.
3. Fajans,Radioelements and Isotopes, etc., 1931, pp. 74–91.
4. Stoner,Magnetism and Matter, 1934, pp. 268 and 269.
5. Ref. 3 Fajans,Radioelements and Isotopes, etc., 1931, pp. 74–91; also Sidgwick,Electronic Theory of Valency, p. 90.