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Curvature conditions and substitution pattern among capital, energy, materials and heterogeneous labour
Koebel, Bertrand M., (1999)
Substitution elasticities between capital, labour, material, electricity and fossil fuels in German producing and service sectors
Koschel, Henrike, (2000)
Rejecting capital-skill complementarity at all costs
Frondel, Manuel, (2001)