BHARGAVA GOPAL. (1992). POLLUTION AND ITS CONTROL. MITTAL PUBLICATIONS.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBHARGAVA GOPAL. POLLUTION AND ITS CONTROL. NEW DELHI: MITTAL PUBLICATIONS, 1992.
एमएलए (9वां संस्करण) प्रशस्ति पत्रBHARGAVA GOPAL. POLLUTION AND ITS CONTROL. MITTAL PUBLICATIONS, 1992.
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