1. Biochemistry and Physiology of copper in vertebrates;O'Dell,1976
2. Deficiency of zinc in man and its toxicity;Prasad,1976
3. Serum copper level as an index of placental function;Friedman;Obstet. & Gyn.,1969
4. Changes in plasma and hair concentrations of zinc, copper, chromium and manganese during pregnancy;Hambidge;Obstet. & Gyn.,1974
5. Fetal and maternal serum copper and zinc levels in human pregnancy;Dreosti;Nutr. Res.,1982