【题 名】：The Consquences of Adjustment for a Concomitant Variable That Has Been Affected by the Treatment            
【作 者】：Paul R. Rosenbaum            
【期刊、会议、单位名称】：Journal of the Royal Statistical Society. Series A (General)            
【年, 卷(期), 起止页码】：Vol. 147, No. 5 (1984), pp. 656-666            
【全文链接】：http://www.jstor.org/pss/2981697