Stevenson, F. J., Bremner, J. M., Hauck, R. D., Keeney, D. R., Dinauer, R. C., Gates, K. E., & Stelly, M. (1982). Nitrogen in agricultural soils (1 edición.). Wisconsin, Estados Unidos: American Society of Agronomy, Inc. ; Crop Science Society of America, Inc. ; Soil Science Society of America, Inc..

Stevenson, Frank J.,, J. M. Bremner, R. D. Hauck, D. R. Keeney, Richard C. Dinauer, Kristine E. Gates, and Matthias Stelly. Nitrogen in Agricultural Soils. 1 edición. Wisconsin, Estados Unidos: American Society of Agronomy, Inc. ; Crop Science Society of America, Inc. ; Soil Science Society of America, Inc., 1982.

Stevenson, Frank J.,, et al. Nitrogen in Agricultural Soils. 1 edición. Wisconsin, Estados Unidos: American Society of Agronomy, Inc. ; Crop Science Society of America, Inc. ; Soil Science Society of America, Inc., 1982.