APA (7th ed.) Citation

Gray, N. F. (1994). Drinking water quality: Problems and solutions. John Wiley.

Chicago Style (17th ed.) Citation

Gray, N. F. Drinking Water Quality: Problems and Solutions. Chichester: John Wiley, 1994.

MLA (9th ed.) Citation

Gray, N. F. Drinking Water Quality: Problems and Solutions. John Wiley, 1994.