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2. Bureau of the Census, (1990b) 1990 CPH-L-74: Age, sex, race, and Hispanic origin information from the 1990 census: A comparison of census results with results where age and race have been modified. Washington, D.C., U.S. Bureau of the Census.
3. Bureau of the Census, (1992) 1990 Census of Population and Housing: Modified age/race, sex and Hispanic origin (MARS) [technical documentation). Washington, D.C., Bureau of the Census.
4. Chatterjee, S. and Price, B. (1977) Regression analysis by example. John Wiley, New York, NY.
5. Cliff, A.D. and Ord, J.K., 1981 Spatial processes: Models and applications. Pion, London.