Chinese Journal of Obstetrics and Gynecology, Volume 46, Issue 12,2011, Pages 901-904, doi:10.3760/cma.j.issn.0529-567x.2011.12.006
Chinese Journal of Obstetrics and Gynecology, Volume 46, Issue 12,2011, Pages 923-927, doi:10.3760/cma.j.issn.0529-567x.2011.12.010
Chinese Journal of Obstetrics and Gynecology, Volume 46, Issue 12,2011, Pages 940-942, doi:10.3760/cma.j.issn.0529-567x.2011.12.015
Chinese Journal of Obstetrics and Gynecology, Volume 46, Issue 12,2011, Pages 960, doi:10.3760/cma.j.issn.0529-567x.2011.12.023
Chinese Journal of Obstetrics and Gynecology, Volume 46, Issue 12,2011, Pages 888-891, doi:10.3760/cma.j.issn.0529-567x.2011.12.003