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East-west trade in wheat : present and potential
Schmidt, Stephen C., (1973)
Der Weizen im Welthandel
Müller-van Ißem, Gerd, (1976)
Săstojanie na proizvodstvoto i tărgovijata s pšenica v Bălgarija
Koteva, Nina, (2003)
Applications of mathematical control theory to finance : modeling simple dynamic cash balance problems
Sethi, Suresh P., (1970)
Simple models in stochastic production planning
Sethi, Suresh P., (1980)
Optimal Control Theory : Applications to Management Science and Economics
Sethi, Suresh P., (2000)