Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 5,2019, Pages 317,
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 5,2019, Pages 312-317, doi:10.3760/cma.j.issn.0529-567x.2019.05.005
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 5,2019, Pages 307-311, doi:10.3760/cma.j.issn.0529-567x.2019.05.004
Chinese Journal of Obstetrics and Gynecology, Volume 54, Issue 5,2019, Pages 358-360, doi:10.3760/cma.j.issn.0529-567x.2019.05.014