Postprint version. Published in Urban Studies, Volume 18, Issue 1, February 1, 1981, pages 133-135.
Copyright © 1981 Sage Publications.
NOTE: At the time of publication, the author David W. Conn was not yet affiliated with Cal Poly.
The definitive version is available at http://dx.doi.org/10.1080/00420988120080171.
Urban, Community and Regional Planning