Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 2,2019, Pages 116-120, doi:10.3760/cma.j.issn.0529-567x.2019.02.007
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 2,2019, Pages 124-125, doi:10.3760/cma.j.issn.0529-567x.2019.02.012
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 2,2019, Pages 103-109, doi:10.3760/cma.j.issn.0529-567x.2019.02.006
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 2,2019, Pages 139-141, doi:10.3760/cma.j.issn.0529-567x.2019.02.016