When was the Heckscher–Ohlin model developed?
Heckscher–Ohlin model
1933
Bertil Ohlin first explained the theory in a book published in 1933. Ohlin wrote the book alone, but he credited Heckscher as co-developer of the model because of his earlier work on the problem, and because many of the ideas in the final model came from Ohlin's doctoral thesis, supervised by Heckscher.