APA-viite

Helmer, R., & Hespanhol, I. (1997). Water Pollution Control: A Guide to the Use of Water Quality Management Principles: Richard Helmer, Ivanildo Hespanhol. Great Britian: St Edmundsbury Press.

Chicago-tyylinen lähdeviittaus

Helmer, Richard, ja Ivanildo Hespanhol. Water Pollution Control: A Guide to the Use of Water Quality Management Principles: Richard Helmer, Ivanildo Hespanhol. Great Britian: St Edmundsbury Press, 1997.

MLA-viite

Helmer, Richard, ja Ivanildo Hespanhol. Water Pollution Control: A Guide to the Use of Water Quality Management Principles: Richard Helmer, Ivanildo Hespanhol. Great Britian: St Edmundsbury Press, 1997.

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