1. Predicting the utilization of helicopter emergency medical services: An approach based on need;Rhee;Ann Emerg Med,1984
2. Medical News editorial: Helicopters and other air ambulances;JAMA,1985
3. Assessment of Utilization and Need. Report to the Massachusetts Department of Health, Division of Determination of Need for EMS Helicopter Transport;Macione,1985
4. American Hospital Association Guide to the Health Care Field;American Hospital Association,1983