1VLEK P L G,STUMPE J M,BYRNES B H.Urease activity and inhibition in flooded soil systems[J].Fert Res,1980,1(3):191-202.
2BREMNER J M,CHAI H S.Evaluation of N-butyl phosphorothioic triamide for retardation of urea hy-drolysis in soil[J].Commun Soll Sci Plant Ana1,1986,17:337-351.
3GRANT C A,JI S,BROWN K R,et al.Volatile losses of urea from surface applied urea ammonium nitrate with and without the urease inhibitor NBPT[J].Can J Soil Sci,1996,76:417-419.
