Barkley, A., & Barkley, P. W. (2013). Principles of agricultural economics. Routledge.
Dyfyniad Arddull ChicagoBarkley, Andrew, and Paul W. Barkley. Principles of Agricultural Economics. London, New York: Routledge, 2013.
Dyfyniad MLABarkley, Andrew, and Paul W. Barkley. Principles of Agricultural Economics. Routledge, 2013.
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