APA citiranje

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.

Trích dẫn kiểu Chicago

Helmer, Richard, và 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 citiranje

Helmer, Richard, và 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.