1. Department Otorhinolaryngology, Hospital Sultanah Aminah, Johor Bahru, Johor, Malaysia
2. Department of Otorhinolaryngology, University of Malaya Faculty of Medicine, Kuala Lumpur
3. Department of Otorhinolaryngology, Hospital Pakar Sultanah Fatimah, Muar, Johor
4. Department of Otorhinolaryngology, Hospital Ampang, Selangor, Malaysia.