1. Department of Dermatology, Hospital of the University of Pennsylvania Perelman School of Medicine at the University of Pennsylvania Philadelphia Pennsylvania USA
2. Section of Pediatric Dermatology, Department of Pediatrics Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
3. Department of Pathology and Laboratory Medicine Children's Hospital of Philadelphia Philadelphia Pennsylvania USA
4. Department of Dermatology, Inselspital University of Berne Bern Switzerland
5. Centro de Dermatología Epidermis Instituto CUF Porto Portugal
6. Dermatology Practice Dermaticum Freiburg Germany