1. National Association of State EMS Officials—Air Medical Services Committee. Brief outline of the federal pre-emption issues in regulating air medical services. October 2011. https://nasemso.org. Accessed July 1, 2016.
2. Federal Aviation Administration. Fact sheet—FAA initiatives to improve helicopter air ambulance safety. February 20, 2014. https://www.faa.gov/news/fact_sheets/news_story.cfm?newsId=15794. Accessed April 1, 2018.
3. CAMTS. http://www.camts.org/Accredited-Services.html. Accessed.
4. US Department of Transportation National Highway Traffic Safety Administration. The 2011 national EMS assessment. June 2014. https://www.ems.gov/pdf/National_EMS_Assessment_Demographics_2011.pdf. Accessed February 10, 2019.
5. Use of a geographic information system to determine appropriate means of trauma patient Transport;Lerner;Acad Emerg Med,1999