Não informado. (1978). Rural Extension, Education and Training Abstracts. Commonwealth Agricultural Bureau.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Rural Extension, Education and Training Abstracts. Farnham Royal, Inglaterra: Commonwealth Agricultural Bureau, 1978.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Rural Extension, Education and Training Abstracts. Commonwealth Agricultural Bureau, 1978.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.