Reference
- Hubbard , D. M. 1937 . Ind. Eng. Chem., Anal. Ed. , 9 : 493
- Du Pont de Nemours . Determining Traces of Lead, Zinc and Chromium in “Coppralyte” Copper Plating Solutions , Delaware : E. I. & Company, Wilmington . (SP 18–649)
- Ross , J. R. and Lucas , C. C. 1935 . J. Biol. Chem. , 3 : 285