GUPTA O P. (2019). Elements of Water Pollution Control Engineering (1st.). KHANNA PUBLICATION.
Lua i Stíl Chicago (17ú heag.)GUPTA O P. Elements of Water Pollution Control Engineering. 1st. NEW DELHI: KHANNA PUBLICATION, 2019.
Lua MLA (9ú heag.)GUPTA O P. Elements of Water Pollution Control Engineering. 1st. KHANNA PUBLICATION, 2019.
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