1. Department of Internal Medicine, Midnapore Medical College and Hospital, Midnapore, WB, India
2. Department of Internal Medicine, RG Kar Medical College and Hospital, Kolkata, India
3. Department of Neurology, Burdwan Medical College and Hospital, Burdwan, WB, India
4. Department of Neurology, Bangur Institute of Neurosciences, IPGMER and SSKM, Kolkata, India