Ohlin, Bertil (bĕrˈtĭl ōˈlĭn) [key], 1899–1979, Swedish economist, b. Klippan. A professor at several Swedish universities, he wrote the influential Interregional and International Trade (1933, rev. ed. 1967), in which he developed the Heckscher-Ohlin principle based on the earlier (1919) work of Eli Heckscher. The theory argues that the types of commodities a nation exports depends entirely on the nation's endowment of resources. His work won him the Nobel Memorial Prize in Economic Sciences in 1977.