1. Hem , J. D. Cropper , W. H. Chemistry of Iron in Natural Water-A Survey of Ferrous-Ferric Chemical Equilibria and Redox Potentials USGS Water Supply Paper 1459-A 1959
2. Hem , J. D. Chemistry of Iron in Natural Water-Restraints on Dissolved Ferrous Iron Imposed by Bicarbonate, Redox Potential, and pH USGS Water Supply Paper 1459-B 1960
3. Hem , J. D. Chemistry of Iron in Natural Water-Complexes of Ferrous Iron With Tannic Acid USGS Water Supply Paper 1459-D 1960
4. Hem , J. D. Chemistry of Iron in Natural Water-Some Chemical Relationships Among Sulfur Species and Dissolved Ferrous Iron USGS Water Supply Paper 1459-C 1960