Krauss, Melvyn B..
Geometric Approach to International Trade / - 1st ed / - Oxford : Basil Blackwell , 1990 - p.96 :
0-631-18470-8
X:54:(B6) / L9;1
Geometric Approach to International Trade / - 1st ed / - Oxford : Basil Blackwell , 1990 - p.96 :
0-631-18470-8
X:54:(B6) / L9;1