6Alan MacPherson. The role of producer service outsourcing in the innovation of New York State manufacturing firms. Annals of the Association of American Geographers. 87 (1) ,pp. 52- 71.1997.
7Beyers,W. B. The producer services and economic development in the United States :The last decade. Economic Development Administration. Technical Assistance and Research Division. U. S. Department of Commerce.Washington. D. C. 1989.
8David P Lindahl,William B Beyers. The creation of competitive advantage by producer service establishments. Economic Geography ,Jan ,Vol. 75, Iss. 1 ; pg. 1,20pgs.
9Goe, W. R. The Growth of Producer Services Industries: Sorting Through the Externalization Debate.Growth and Change 22:118-41.
10Hansen,Niles. Do Producer services induce regional economic development?. Journal of Regional Science,Nov90,Vol. 30 Issue 4,p465,12p,2 charts.