References AMITI, Mary, KHANDELWAL, Amit K. Import Competition and Quality Upgrading. NBER Working Paper Series, No. 15503, November 2009. ARMINGTON, Paul S. A Theory of Demand for Products Distinguished by Place of Production. International Monetary und Staff Papers, vol. 16, No. 1, March 1969, pp. 159–178. BLONIGEN, Bruce A., SODERBERY, Anson. Measuring the Benefits of Product Variety with an Accurate Variety Set. NBER Working Paper Series, No.14956, May 2009. BRODA, Christian, WEINSTEIN, David E. Globalization and the Gains from Variety. Quarterly Journal of Economics, vol. 121, No. 2, May 2006, pp. 541–585. DENNIS, Allen, SHEPHERD, Ben. Trade Costs, Barriers to Entry, and Export Diversification in Developing Countries. World Bank Policy Research Working Paper, No. 4368, September 2007. DIXIT, Avinash K., STIGLITZ, Joseph E. Monopolistic Competition and Optimum Product Diversity. American Economic Review, vol. 67, No. 3, June 1977, pp. 297–308. FEENSTRA, Robert C. New Product Varieties and the Measurement of International Prices. American Economic Review, vol. 84, No. 1, March 1994, pp. 157–177. FEENSTRA, Robert C., KEE, Hiau Looi. Export Variety and Country Productivity. NBER Working Paper Series, No. 10830, October 2004. FEENSTRA, Robert C., KEE, Hiau Looi. On the Measurement of Product Variety in Trade. American Economic Review, vol. 94, No. 2, May 2004, pp. 145–149. FLAM, Harry, HELPMAN, Elhanan. Vertical Product Differentiation and North-South Trade. American Economic Review, vol. 77, No. 5, December 1987, pp. 810–822. FUNKE, Michael, RUHWEDEL, Ralf. Export Variety and Economic Growth in East European Transition Economies. BOFIT Discussion Papers, No. 8, 2003. HALLAK, Juan Carlos, SCHOTT, Peter K. Estimating Cross-Country Differences in Product Quality. NBER Working Paper Series, No. 13807, February 2008. HUMMELS, David, KLENOW, Peter J. The Variety and Quality of a Nation's Exports. American Economic Review, vol. 95, No. 3, June 2005, pp. 704–723. KRUGMAN, Paul R. Increasing Returns, Monopolistic Competition, and International Trade. Journal of International Economics, vol. 9, No. 4, November 1979, pp. 469–479. KRUGMAN, Paul R. Scale Economies, Product Differentiation, and the Pattern of Trade. American Economic Review, vol. 70, No. 5, December 1980, pp. 950–959. KRUGMAN, Paul R. Intraindustry Specialization and the Gains from Trade. Journal of Political Economy, vol. 89, No. 5, October 1981, pp. 959–973. LEAMER, Edward E. Is it a Demand Curve, or is it a Supply Curve? Partial Identification through Inequality Constraints. Review of Economics and Statistics, vol. 63, No. 3, August 1981, pp. 319–327. SATO, Kazuo. The Ideal Log-Change Index Number. Review of Economics and Statistics, vol. 58, No. 2, May 1976, pp. 223–228.