1. Comfort A. The biology of senescence. 3rd ed. New York: Elsevier; 1979. 414 p.
2. Strehler BL. Time, cells, and aging. New York: Academic; 1962. 270 p.
3. I D. Theories and general principles of aging. In: Brocklehurst JC, Fillit HM, editors. . Edinburgh: Churchill Livingstone; 1992. p. 26–60.
4. Dalziel KLBD. Skin aging. In: Brocklehurst JC, Fillit HM, editors. Textbook of geriatric medicine and gerontology. Edinburgh: Churchill Livingstone; 1992. p. 898–921.
5. Kenney WL, Fowler SR. Methylcholine-activated eccrine sweat gland density and output as a function of age. J Appl Physiol (1985). 1988;65:1082–6.