244 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 REFERENCES i. H.C. Bos and J. TINBERGEN, Mathematical Models of Economic Growth, New York, 1962. 2] W. Isarp and E. SMOLENSKY, Application of Input-Output Techniques to Regional Science, in: « Structural Interdependence and Economic Development ». (Tibor Barna, ed.). London, 1963, p. 105. 3] W. LEONTIEF and A. STROUT, Multiregional Input-Output Analysis in: « Structural Interdependence and Economic Development ». (Tibor Barna, ed.). London, 1963, p. 119. 4] J. TINBERGEN, Regionaal-economische planning, Seminarie voor Toege- paste Economie bij de Rijks-Universiteit te Gent, Gent 1961. 5] J. TINBERGEN, Planning in Stages, Statsgkonomisk Tidsskrift, 1962, p. 1. 6] J. TINBERGEN, De optimale organisatie der economische beslissingen. Mededelingen der Kon. Ned. Akad. v. Wetenschappen. afd. Letter- kunde, Nieuwe reeks - Deel 24 - No. =~ 1o| Tinbergen - pag. 12