各位朋友，由于本人所在学校未购买JSTIOR，故向大家求助两篇论文：
1.Pred A R, 1975, "Diffusion, organizationalspatial structure and city system development". Economic Geography 51252-268 2.Meir A. (1981) Innovation diffusion andregional economic development: the spatial diffusion of automobiles in Ohio, Regional Studies15, 111—122.
    为表示感谢，每篇支付15论坛币。先谢谢了！