Bloom et al. Journal of the American Chemical Society, 1957 , vol. 79, p. 5072 Full Text Show Details Pfizer and Co. Patent: US2811529 , 1956 ; Full Text Show Details Pfizer and Co. Patent: US2889351 , 1957 ; Full Text Show Details Najer et al. Bulletin de la Societe Chimique de France, 1959 , p. 352,355