另求Bergstrand, J.H. (1985), The gravity equation in international trade: some microeconomic foundations and empirical evidence,文献一篇。


压缩包里有：
  Deardorff 1995 does gravity work in a neoclassical world
   J.E.Anderson 1979 A theoretical foundation for the gravity equation 引力模型开山巨作 50论坛币买的
   J.E.Anderson E.Wincoop 2001 Gravity with gravitas:A solution to the border puzzle
    J.E.Anderson E.Wincoop 2004 Trade cost
几篇都是经典文献，象征性的收点。