1. Vitamin D and bone health in the elderly;Parfitt;Am. J. Clin Nutr.,1982
2. Vitamin D synthesis by the aging skin;Holick,1986
3. Aging decreases the capacity of human skin to produce vitamin D;MacLaughlin;J. Clin. Invest.,1985
4. Age, vitamin D, and solar ultraviolet;Holick;Lancet,1989
5. Intestinal cholecalciferol absorption in the elderly and in younger adults;Baragry;Clin. Sci. Mol. Med.,1978