by Ronald R. Piening ; editors, Jane Ruhland, C.W. Threinen, Ruth Hine ; copy editor, Lori Goodspeed ; graphic artists, Nina Lusterman, Kathy Bruch, Richard Burton ; word processor, Sue Hoffman
"An expanded and updated version of the first edition compiled in 1961 by Ronald J. Poff and C.W. Threinen; data for second edition collected 1976-77."
"Lake and stream classification project."
Includes bibliographical references (pages 68-69).