1. Center for Studying Health Systems Change Hospital Emergency On-call Coverage: Is There a Doctor in the House? http://www.hschange.com/CONTENT/956/956.pdf
2. The American College of Surgeons A Growing Crisis in Patient Access to Emergency Surgical Care The American College of Surgeons, Division of Health Advocacy and Health Policy http://www.facs.org/ahp/emergcarecrisis.pdf
3. The on-call crisis: a statewide assessment of the costs of providing on-call specialist coverage;McConnell;Ann Emerg Med.,2007