BMC Pregnancy and Childbirth, Volume 13, Year 2013
BMC Public Health, Volume 12, No. 1, Year 2012
BMC Public Health, Volume 11, Year 2011
BMC Pregnancy and Childbirth, Volume 15, No. 1, Year 2015
BMC Health Services Research, Volume 15, No. 1, Year 2015
BMC Women's Health, Volume 14, No. 1, Year 2014