Nitrogen in agricultural soils - Stevenson, Frank J.,; Bremner, J. M.,; Hauck, R. D.,; Keeney, D. R.,; Dinauer, Richard C.,; Gates, Kristine E.,; Stelly, Matthias, (American Society of Agronomy, Inc. ; Crop Science Society of America, Inc. ; Soil Science Society of America, Inc., 1982)