1. Contracting for Emergency Ambulance Services — A Guide to Effective System Design,1999
2. Büch, E., Koch, B., 1998. Wirtschaftlichkeit im Rettungsdienst, Institut für Rettungsdienst des Deutschen Roten Kreuzes, Schriftenreihe zum Rettungswesen, Vol. 18, Nottuln.
3. Tentative classification of emergency situations;Cara,1981
4. The effect of EMS system factors on trauma survival;Cayten,1992
5. Response time and the location of emergency medical facilities in rural areas: a case study;Daberkov;American Journal of Agricultural Economics,1977