1. Pool Officer, Department of Otolaryngology, Medical College Hospitals, Calcutta, India.
2. Reader, Department of Otolaryngology, Medical College Hospitals, Calcutta, India.
3. Professor and Head, Department of Otolaryngology, Medical College Hospitals, Calcutta, India.
4. Consultant Pathologist, Roy & Trivedi Pathological Centre, Calcutta, India.