1. U.S. Department of Health and Human Services. The State of the National Vaccine Plan 2013 Annual Report: Protecting the Nation's health through immunization. Available at: http://www.hhs.gov/nvpo/vacc_plan/annual-report-2013/nvp-2013.html [accessed 08.01.15].
2. Occupational licensing: a framework for policy makers,2015
3. Reforming health care workforce regulation: policy considerations for the 21st century. Report of the Taskforce on Health Care Workforce Regulation;Pew Health Professions Committee,1995
4. Relaxing occupational licensing requirements: analyzing wages and prices for a medical service. NBER Working Paper No 19906;Kleiner,2014
5. Mandatory licensing of registered nurses: introduction and impact. Occupational licensure and regulation;White,1980