1. A Theory of Demand for Products Distinguished by Place of Production;P S Armington;IMF Staff Papers,1969
2. A Theoretical Foundation for the Gravity Equation;James E Anderson;American Economic Review,1979
3. Gravity with Gravitas: A Solution to the Border Puzzle;James E Anderson;American Economic Review,2003
4. The Gravity Equation in International Trade: Some Microeconomic Foundations and Empirical Evidence;Jeffrey H Bergstrand;Review of Economics and Statistics,1985
5. The Generalized Gravity Equation, Monopolistic Competition, and the Factor-Proportions Theory in International Trade;Jeffrey H Bergstrand;Review of Economics and Statistics,1989