1. 1. Vaughan HF Gamester C: Why patients use emergency departments. Hospitals 1966; 40:59-62 121.
2. 2. Lavanhar M Ratner R Weinerman E: Social class and medical care: Indices of nonurgency in use of hospital emergency services. Medical Care 1968; 6:368-380.
3. 3. Gibson G: EMS: A facet of ambulatory care. Hospitals 1973; 47:47-66.
4. 4. Davidson SM: Understanding the growth of emergency department utilization. Medical Care 1978; 15:121-132.
5. 5. Coleman JV Errera P: The general hospital emergency room and its psychiatric problems. Am J Pub Health 1963; 53:1294-1301.