Societal responses for addressing nitrogen fertilizer needs: Balancing food production and environmental concerns - Palm, Cheryl; Machado, Pedro L.; Mahmood, Tariq; Melillo, Jerry; Murrell, Scott T.; Nyamanagra, Justice; Scholes, Mary; Sisworo, Elsje; Olsen, Jorgen E.; Pender, John L.; Stewart, John; Galloway, James N. (Island Press, 2004)