Singh, B. D. Environmental management: A geographical study of Sultanpur district. Deep and Deep Pubs. 1992.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रSingh, Beena Devi. Environmental Management: A Geographical Study of Sultanpur District. Deep and Deep Pubs. 1992.
एमएलए (9वां संस्करण) प्रशस्ति पत्रSingh, Beena Devi. Environmental Management: A Geographical Study of Sultanpur District. Deep and Deep Pubs. 1992.
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