Chinese Journal of Obstetrics and Gynecology, Volume 47, Issue 9,2012, Pages 669-671, doi:10.3760/cma.j.issn.0529-567x.2012.09.007
Chinese Journal of Obstetrics and Gynecology, Volume 47, Issue 9,2012, Pages 651-654, doi:10.3760/cma.j.issn.0529-567x.2012.09.003
Chinese Journal of Obstetrics and Gynecology, Volume 47, Issue 9,2012, Pages 664-668, doi:10.3760/cma.j.issn.0529-567x.2012.09.006
Chinese Journal of Obstetrics and Gynecology, Volume 47, Issue 9,2012, Pages 684-685, doi:10.3760/cma.j.issn.0529-567x.2012.09.011
Chinese Journal of Obstetrics and Gynecology, Volume 47, Issue 9,2012, Pages 716-718, doi:10.3760/cma.j.issn.0529-567x.2012.09.022