1. CONTEMPORARY TRENDS IN THE REGIONAL ECONOMIC DEVELOPMENT OF THE UNITED STATES
2. W. B. Beyers, 1989 .The producer services and economic development in the United States: the last decade. Final report prepared for the Technical Assistance and Research Division, U.S. Department of Commerce Economic Development Administration.
3. W. B. Beyers, 1989 . Explaining the growth of the producer services in the United States, 1974-1985 . A paper presented at the Regional Science Association Meetings.