1. Newkirk, A. E. , “Preparation and Chemistry of Elementary Boron,” 135th Am. Chem. Soc. Meeting, Symposium on Boron, April 1959.
2. Powell, C. F. , I. E. Cambell, and B. W. Gonser, Vapor Plating, John Wiley and Sons (New York), 1955.
3. Pfann, W. G. , Zone Melting, John Wiley and Sons (New York), 1958.
4. Lawson, W. D. , and S. Nielsen, Preparation of Single Crystals, Academic Press (New York), 1958.
5. Calverly, A. , M. Davis, and R. F. Lever, “The Floating Zone Melting of Refractory Metals by Electron Bombardment,” J. Sci. Instr. 34:142 (1957).