1. Department of Surgery, Penn State Hershey College of Medicine and Milton S. Hershey Medical Center, Hershey
2. Department of Public Health Services, Penn State Hershey College of Medicine and Milton S. Hershey Medical Center, Hershey
3. Department of Surgery, University of Southern California, Los Angeles
4. Department of Medicine, Penn State Hershey College of Medicine and Milton S. Hershey Medical Center, Hershey