Ward, R. C. (1967). Principles of hydrology. McGraw-Hill.
Chicago Style aipamenaWard, R C. Principles of Hydrology. Newyork: McGraw-Hill, 1967.
MLA aipamenaWard, R C. Principles of Hydrology. McGraw-Hill, 1967.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.