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孙政才, 陈国平, 汪学才, 张文诗, 刘永贵, 周长宝
N. P. K. Application for Winter Wheat-Summer Maize Double Cropping System in Beijing Suburbs
Sun Zhengcai, Chen Guoping
华北农学报 . 1993, (4): 99 -105 .  DOI: 10.3321/j.issn:1000-7091.1993.04.020