5Huimin Zhang, Minggang Xu, Fusuo Zhang.Long-term ef- fects of manure application on grain yield under different cropping systems and ecological conditions in China [J]. The Journal of Agricultural Science, 2009, 147 (1) : 31--42.
6Hao M D, Fan Wang J J.Wheat term fertilization dosphere, 2007, J, Wang Q J, Dang T H, Guo S L, grain yield and yield stability in a long- experiment on the Loess Plateau [J]. Pe- 17 (2): 257-264.
