1. Anderson, James E., “A Theoretical Foundation for the Gravity Equation”.The American Economic Review, Vol. 69, 1979, pp. 106–116.
2. Armington, Paul S., “A Theory of Demand for Products Distinguished by Place of Production”.IMF Staff Papers, Vol. 16, 1969, pp. 159–178.
3. Bradley, Jane A., “Intellectual Property Rights, Investment and Trade in Services in the Uruguay Round: Laying the Foundations”.Stanford Journal of International Law, Vol. 23, 1987, pp. 57–98.
4. Caves, Richard E.,Multinational Enterprise and Economic Analysis. Cambridge 1982.
5. Contractor, Farok J., “Licensing versus Foreign Direct Investment in U.S. Corporate Strategy: An Analysis of Aggregate U.S. Data”. In: Nathan Rosenberg, Claudio Frischtak (Eds.),International Technology Transfer: Concepts, Measures and Comparisons. New York 1985, pp. 277–320.