Puu, T. (1980). The economics of technological progress: Proceedings of a conference held by the European Production Study Group in Umeå, Sweden, 23-25 August 1978 : including a bibliography on the subject. London: Macmillan.
Trích dẫn kiểu ChicagoPuu, Tonu. The Economics of Technological Progress: Proceedings of a Conference Held By the European Production Study Group in Umeå, Sweden, 23-25 August 1978 : Including a Bibliography On the Subject. London: Macmillan, 1980.
Trích dẫn MLAPuu, Tonu. The Economics of Technological Progress: Proceedings of a Conference Held By the European Production Study Group in Umeå, Sweden, 23-25 August 1978 : Including a Bibliography On the Subject. London: Macmillan, 1980.
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