1. Hayflick, L. 1970. Aging under glass. Exp. Geront. 5: 291.
2. Cristofalo, V.J. 1972. Animal cell cultures as a model. system for the study of aging. Adv. Gerontol, 4: 45.
3. Hughes, R.C. 1973.` IN: Progress in Biophysics and Molecular Biology (Buttler and B. Nobles editors), Pergamon Press, 26: 189.
4. Nonnan, K.D., Levine, A.J., and Burger, I. 1973. Cell cycledependent changes in the surface membrane as detected with 3H-concanavalin A. J. Cell. Biol. 58: 491.
5. Shoham,J., Sachs, L. 1974. Different cyclic changes in the surface membrane of normal and malignant transformed cells. Exp.. Cell. es. 85: 8, 1974.