Total hip replacement and bipolar hemiarthroplasty for femoral neck fracture in the elderly: A Meta analysis 
Li Guo-wei, Dong Ming-yan, Zhang Hai-fei, Yan Xue
Chinese Journal of Tissue Engineering Research . 2011, (22): 4061 -4064 .  DOI: 10.3969/j.issn.1673-8225.2011.22.017