Troeh, Frederick Soil and water conservation for productivity and environmental protection by Frederick R. Troeh, J. Arthur Hobbs and Roy L. Donahue - Englewood Cliffs Prentice-Hall 1980 - xv, 718p. ISBN: 0-13-822155-3 Subjects--Topical Terms: Soil conservationwater conservation Dewey Class. No.: 631.7 / TRO/S