00397naa a2200121 a 450000100080000000500110000800800410001910000140006024501060007426000090018070000140018977300720020318272712010-01-10       1975    bl ---       0--  u    #d1 aSINGH, K.  aEffect of levels and sources of nitrogen on wheatbyield components, yield and fertilizer efficiency.  c19751 aSINGH, M.  tIndian Journal of Agronomy, New Delhigv. 20, n. 1, p. 35-40, 1975.