Chinese Journal of Obstetrics and Gynecology, Volume 53, Issue 7,2018, Pages 481-486, doi:10.3760/cma.j.issn.0529-567x.2018.07.007
Chinese Journal of Obstetrics and Gynecology, Volume 53, Issue 7,2018, Pages 459-463, doi:10.3760/cma.j.issn.0529-567x.2018.07.004
Chinese Journal of Obstetrics and Gynecology, Volume 53, Issue 7,2018, Pages 508-510, doi:10.3760/cma.j.issn.0529-567x.2018.07.015
Chinese Journal of Obstetrics and Gynecology, Volume 53, Issue 7,2018, Pages 448-451, doi:10.3760/cma.j.issn.0529-567x.2018.07.002