1. Kaufman, Fankuchen and Mark, J. Chem. Phys., 15, 414 (1947).
2. American Society for X-Ray and Electron Diffraction, Quebec (June 1947).
3. 11th International Congress of Pure and Applied Chemistry, London (July 1947).
4. American Chemical Society, New York (September 1947).
5. Lippincott and Lord, J. Amer. Chem. Soc., 68, 1868 (1946).