Niederl; Natelson; Beekman Journal of the American Chemical Society, 1933 , vol. 55, p. 2571,2574 Full Text Show Details Roehm and Haas Co. Patent: US2008032 , 1933 ; Full Text Show Details Roehm and Haas Co. Patent: US2008337 , 1932 ; Full Text Show Details Roehm and Haas Co. Patent: DE666134 , 1933 ; Fortschr. Teerfarbenfabr. Verw. Industriezweige, vol. 24, p. 172,25 137 Full Text Show Details Roehm and Haas Co. Patent: DE657724 , 1934 ;