CHINESE JOURNAL OF PERINATAL MEDICINE, Volume 12, Issue 5,2009, Pages 367-370, doi:10.3760/cma.j.issn.1007-9408.2009.05.012
CHINESE JOURNAL OF PERINATAL MEDICINE, Volume 12, Issue 5,2009, Pages 373-375, doi:10.3760/cma.j.issn.1007-9408.2009.05.014
CHINESE JOURNAL OF PERINATAL MEDICINE, Volume 12, Issue 5,2009, Pages 342-345, doi:10.3760/cma.j.issn.1007-9408.2009.05.006
CHINESE JOURNAL OF PERINATAL MEDICINE, Volume 12, Issue 5,2009, Pages 382-384, doi:10.3760/cma.j.issn.1007-9408.2009.05.018