Prescott, G. W. How to know the freshwater algae G. W. Prescott. - 3d ed. - Dubuque, Iowa W. C. Brown c1978. - x, 293 p. ill. 23 cm. - The Pictured key nature series . Includes index. Bibliography: p. 15-16. ISBN: 0697047555. 0697047547 LCCN: 77091275 //r85 Subjects--Topical Terms: Freshwater algae--Identification. LC Class. No.: QK567 / .P7 1978 Dewey Class. No.: 589/.39/29