Cohen et al. Journal of the American Chemical Society, 1959 , vol. 81, p. 5508 Journal of the American Chemical Society, 1960 , vol. 82, p. 2731,2733,2734 Full Text View citing articles Show Details Merck and Co. Inc. Patent: US2952680 , 1958 ; Full Text Show Details Merck and Co. Inc. Patent: US2910488 , 1958 ;