Gupta, S. (1999). International encyclopaedia of global environment and social development: Environment and social issues. Sarup & sons.
Trích dẫn kiểu ChicagoGupta, Sunit. International Encyclopaedia of Global Environment and Social Development: Environment and Social Issues. New Delhi: Sarup & sons, 1999.
Trích dẫn MLAGupta, Sunit. International Encyclopaedia of Global Environment and Social Development: Environment and Social Issues. Sarup & sons, 1999.
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