1. Department of Otorhinolaryngology and Head and Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India
2. Department of Surgical Oncology, All India Institute of Medical Sciences, Rishikesh, India
3. Department of General Surgery, All India Institute of Medical Sciences, Mangalagiri, India
4. Department of General Surgery, Dr. Pinnamaneni Siddhartha Institute of Medical Sciences and Research Foundation, Vijayawada, India