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3. V. I. Mikheeva, Transition Metal Hydrides (Izd. Akad. Nauk SSSR, Moscow, 1960), p. 211 [in Russian].
4. L. K. Lepin’ and N. Tetere, Dokl. Akad. Nauk SSSR 90, 413 (1953).
5. L. K. Lepin’, Izv. Akad. Nauk Latv. SSR, Ser. Khim., No. 8, 79 (1960).