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Heterogeneity, control variables, and maximizing behaviour : theory and an application to earnings functions with labor mobility
Hübler, Olaf, (1986)
Resource allocation for small scalf farmers of the star grass zone in Embu District, Kenya : a linear programming approach
Asamenew, G., (1985)
Schnittebenenverfahren für Travelling-Salesman- und verwandte Probleme
Holland, Olaf A., (1987)