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Demographic conditions responsible for population aging
Preston, Samuel H., (1989)
Old-age mortality patterns in low-mortality countries : an evaluation of population and death data at advanced ages, 1950 to the present
Condran, Gretchen A., (1991)
A longitudinal analysis of urban poverty : blacks in the US metropolitan areas between 1970 and 1980
Eggers, Mitchell L., (1992)