Speare, Alden Jr, and William H. Frey. "Metropolitan Areas of the Future: Issues and Definitions." 1991 Proceedings of the Government Statistics Section of the American Statistical Association, 1991. Reprint No. 373.
U.S. urbanization patterns have changed markedly between 1950 and the present. It is important to evaluate these changes when formulating plans for a new metropolitan definition. In this paper, we discuss ways U.S. urbanization is evolving, limitations of the current metropolitan concept, and aspects of a new metropolitan area concept we have begun to examine.