On-farm soil N supply and N nutrition in the rice-wheat system of Nepal and Bangladesh - Adhikari, C.; Bronson, K.F.; Panuallah, G.M; Regmi, A.P; Saha, P.K; Dobermann, A.; Olk, D.C.; Hobbs, P.R; Pasuquin, E. (Elsevier, 1999)