1. U S Bureau of the Census, 1991. PESDSES.DAT, computer file, 15 April. Washington, DC.
2. U.S. Department of Commerce, 1990. ‘1990 Census Population for the United States is 249,633.692;
3. General Accounting Office, 1991d. ‘1990 Census: Final Preparations for a Possible Adjustment’, Statement of L. Nye Stevens before the Subcommittee on Government Information and Regulation, Committee on Governmental Affairs, United States Senate.