Barbier, E. B. (1987). Cash crops, food crops and agricultural sustainability.
Cita Chicago (17th ed.)Barbier, Edward B. Cash Crops, Food Crops and Agricultural Sustainability. 1987.
Cita MLA (9th ed.)Barbier, Edward B. Cash Crops, Food Crops and Agricultural Sustainability. 1987.
Atenció: Aquestes cites poden no estar 100% correctes.