1. Renal Division, Department of Internal Medicine, Barnes‐Jewish Hospital, Washington University School of Medicine, St. Louis, Missouri, U.S.A.
2. Division of Bone and Mineral Diseases, Department of Internal Medicine, Barnes‐Jewish Hospital, Washington University School of Medicine, St. Louis, Missouri, U.S.A.
3. G.D. Searle Research an Development, Monsanto Company, St. Louis, Missouri, U.S.A.