1. General: E. A. van Arkel. Reine Metalle [Pure Metals], Berlin, 1939;
2. H. Funk. Darstellung der Metalle im Laboratorium [Laboratory Preparation of Metals], Stuttgart, 1938;
3. C. A. Hampel. Rare Metals Handbook, New York, 1964.
4. Metallic Thorium1
5. Production of Ductile Vanadium by Calcium Reduction of Vanadium Trioxide