Ward, R C. Principles of hydrology/ R C Ward. - 4th ed. - London ; Burr Ridge, Ill. : McGraw-Hill, ©2000. - xiv, 450p.: ill., maps; 25cm. includes bibliographical references and index. ISBN: 9780077095024 Subjects--Topical Terms: Hydrology. LC Class. No.: GB661 / WAR2000