1. University of Minnesota Medical School Minneapolis MN USA
2. Mayo Clinic Alix School of Medicine Rochester MN USA
3. Health Sciences Library University of Minnesota Minneapolis MN USA
4. Department of Internal Medicine University of Minnesota Minneapolis MN USA
5. Department of Dermatology University of Minnesota Minneapolis MN USA
6. Department of Internal Medicine Minneapolis VA Health Care System Minneapolis MN USA
7. Department of Dermatology Minneapolis VA Health Care System Minneapolis MN USA
8. Department of Dermatology Mayo Clinic Rochester Minnesota USA