Purcell, D., & Anderson, J. R. (1997). Agricultural extension and research: Achievements and problems in national systems. Washington, D.C.: World Bank.
Παραπομπή Chicago StylePurcell, Dennis, και Jock R. Anderson. Agricultural Extension and Research: Achievements and Problems in National Systems. Washington, D.C.: World Bank, 1997.
Παραπομπή MLAPurcell, Dennis, και Jock R. Anderson. Agricultural Extension and Research: Achievements and Problems in National Systems. Washington, D.C.: World Bank, 1997.
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