PLoS ONE, Volume 9, No. 4, Year 2014
BMC Pregnancy and Childbirth, Volume 12, Year 2012
PLoS ONE, Volume 13, No. 5, Year 2018
PLoS ONE, Volume 10, No. 3, Year 2015
BMC Health Services Research, Volume 13, No. 1, Year 2013
PLoS ONE, Volume 12, No. 1, Year 2017