1. WHO. World health statistics 2010. Available at http://www.who.int/whosis/whostat/EN_WHS10_Full.pdf [accessed 20.09.11].
2. Migration as a risk factor for measles after a mass vaccination campaign, Burkina Faso, 2002;Yaméogo;Int J Epidemiol,2004
3. News report on the low coverage of measles vaccination and high outbreak rates among migrant children. Data released by China Center for Disease Control. Available at http://health.sohu.com/20110520/n308103751.shtml [in Chinese, accessed 20.09.11].
4. Press release on major figures of the 2010 national population census. Available at http://www.stats.gov.cn/was40/gjtjj_en_detail.jsp?searchword=Census&channelid=9528&record=8 [accessed 12.04.12].
5. A comparative study on immunization coverage rates of nine vaccines between local and floating children;Liu;Chin J Vaccines Immunization,2007