Nitrogen in crop production : proceedings of a symposium held 25-27 May 1982 at Sheffield, Alabama / sponsored by the National Fertilizer Development Center of the Tennessee Valley Authority ... [et al.] ; Roland D. Hauck, editor-in-chief. Hauck, Roland Daniel, 1926- National Fertilizer Development Center (U.S.) American Society of Agronomy. Nitrogen fertilizers Congresses. Plants Effect of nitrogen on Congresses. Crops Nutrition Congresses. S651 .N58 1984 631.84 N731 Includes bibliographies and index. Madison, Wis. : American Society of Agronomy, 1984. 1984. 1984 Text xxv, 804 p. : eng