1. Transition Metal Carbides and Nitrides;Toth,1971
2. U.S. Patent 3,253,886 (1966), to Union Carbide Corp.; Chem. Abstr., 65 (1966) PC5196a.
3. U.S. Patent 3,848,062 (1974), to PPG Industries, Inc.; Chem. Abstr., 82 (1975) P45945W.
4. Production of tungsten carbide powder from the vapor phase