7MARSHALL A. Principles of Economics [ M ]. London : Macmillan press, 1920.
8KOLKO J. Agglomeration and Co - Agglomeration of Services Indus- tries [D]. San Francisco: Public Policy Institute of California, 2007.
9GIACINTO V D, MARCELLO P. Local and global agglomeration pat- terns: Two econometrics- based indicators [ J ]. Regional Science and Urban Economics, 2011 (41) : 266 -280.
10SHEARMUR R, DOLOREUX D. Urban Hierarchy or Local Buzz? High - Order Producer Service and (or) Knowledge - Intensive Busi- ness Service Location in Canada, 1991 - 2001 [ J ]. The Professional Geographer, 2008, 60 (3): 1143-1163.
