Elson E C, Ivor L, Gochman N
Am J Clin Pathol. 1978 Mar;69(3):354-5. doi: 10.1093/ajcp/69.1.354.
Because of the possible carcinogenicity of benzidine, a plasma hemoglobin method that substitutes reagents now used in other methods and poses no similar hazard is presented. It is comparable to the benzidine method in ease and time of accomplishment.