Dietary restriction and aging: The initiation of a primate study. - Ingram,D.K.; Cutler,R.G.; Weindruch,R.; Renquist,D.M.; Knapka,J.M.; April,M.; Belcher,C.T.; Clark,M.A.; Hatcherson,C.D.; Marriott,B.M.; Roth,G.S. (J Gerontol Biol Sci, 1990)