Managing nitrogen for groundwater quality and farm profitability: proceedings of a symposium sponsored by Division A-5 of the American Society of Agronomy; S-1, S-3, S-4, S-6, and S-8 of the Soil Science Society of America; and Divisions C-3 and C-5 of the Crop Science Society of America, Anaheim, CA, 1988 - Follett, R. F.; Keeney, Dennis R; Cruse, R. M. (Soil Science Society of America, 1991)