1. Department of Neurosurgery, NRS Medical College and Hospital, Kolkata, West Bengal, India
2. Department of Neurosurgery, Calcutta National Medical College and Hospital, Kolkata, West Bengal, India
3. Department of Community Medicine, Calcutta National Medical College, Kolkata, West Bengal, India
4. Department of Pathology, Calcutta National Medical College, Kolkata, West Bengal, India