Singh, A. (2003). Encyclopedia of teaching of environmental sciences, Vol. 2. Anmol.
Chicago-čujuhus (17. p.)Singh, A.K. Encyclopedia of Teaching of Environmental Sciences, Vol. 2. NewDelhi: Anmol, 2003.
MLA-čujuhus (9. p.)Singh, A.K. Encyclopedia of Teaching of Environmental Sciences, Vol. 2. Anmol, 2003.
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