8Anderson, J.E. A Theoretical Foundation for the Gravity Equation[J]. American Economic Review,1979, 69, 106-116.
9Anderson, J.E. and Wincoop. E. Gravity with Gravitas:A Soulution to the Border Puzzle[J].American Economic Review,2003,93,170-192.
10Anderson,M. and Smith,S. Do National Borders Really Matter Canada-U. S Regional Trade Re considered[J],Review of International Economics,1999,7,219-227.