Metal-metal surface hip replacement versus total hip replacement: 18-month follow-up in young patients and those having many activities  
Liang Zhi-quan, Ai Li-jiang•A Si-la, Meng Qing-cai, Lu Yong, Fang Rui
Chinese Journal of Tissue Engineering Research . 2012, (9): 1547 -1550 .  DOI: 10.3969/j.issn.1673-8225.2012.09.007