Feder, G., Willett, A., & Zijp, W. (1999). Agricultural extension: Generic challenges and the ingredients for solutions. World Bank.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रFeder, Gershon, Anthony Willett, और Willem Zijp. Agricultural Extension: Generic Challenges and the Ingredients for Solutions. Washington, D.C: World Bank, 1999.
एमएलए (9वां संस्करण) प्रशस्ति पत्रFeder, Gershon, et al. Agricultural Extension: Generic Challenges and the Ingredients for Solutions. World Bank, 1999.
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