Du Pont de Nemours and Co.
Patent: US2416042 , 1944 ;

Agafonov, N. E.; Kondrat'eva, G. Ya.
Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1985 , vol. 34, # 7 p. 1474 - 1477
Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1985 , # 7 p. 1612 - 1615

Bittner, Andreas J.; Rademacher, Paul Journal of Chemical Research, Miniprint, 1991 ,  # 3  p. 555 - 580