1. Assad R Levison D 2013 Employment for youth: a growing challenge for the global economy. Background research paper submitted to the High Level Panel on the Post-2015 Development Agenda http://www.post2015hlp.org/wp-content/uploads/2013/06/Assaad-Levison-Global-Youth-Employment-Challenge-Edited-June-5.pdf
2. A comparison of response to mailed questionnaires and telephone interviews in a mixed mode health survey;Brambrilla;American Journal of Epidemiology,1987
3. Proactive personality and the successful job search: a field investigation with college graduates;Brown;Journal of Applied Psychology,2006
4. Centers for Disease Control and Prevention 2017 Data for health initiative http://www.cdc.gov/globalhealth/healthprotection/data.html
5. To mix or not to mix data collection modes in surveys;De Leeuw;Journal of Official Statistics,2005