1. National Distillers and Chemical Corp., US Patent No. 3222290 (1962);
2. J. Soc. Dyers Col.,83, 126 (1967).
3. M. Tibu, I. Viserian, B. Arvertiev, H. Offenberg, and T. Nicolaescu, Analete Stiint. Univ. A. I. Cuza, Iasi Sect. I,9, 261 (1963); Chem. Abstr.,60, 2434 (1964).
4. Yu. N. Panov, N. A. Adrova, and M. M. Koton, Opt. i Spektrosk.,7, 29 (1959).
5. D. G. Ott, F. N. Hayes, E. Hansbury, and V. N. Kerr, J. Amer. Chem. Soc.,79, 5448 (1957).