1. Department of Environmental Health Sciences University of Michigan School of Public Health Ann Arbor Michigan
2. Wayne State University School of Medicine and Karmanos Cancer Institute Detroit Michigan
3. Department of Otorhinolaryngology Faculty of Medicine Khon Kaen University Thailand
4. Khon Kaen Head and Neck Oncology Research Khon Kaen University Thailand
5. Songkhla Cancer Registry Prince of Songkla University Songkhla Thailand