1. Gondwana Palaeobiology, Birbal Sahni Institute of Palaeosciences, Lucknow, India
2. Coal Petrology, Geological Survey of India, State Unit: Manipur and Nagaland, Dimapur, India
3. Paleobotany, Senckenberg Forschungsinstitut und Naturmuseum Frankfurt, Frankfurt, Germany
4. Coal Petrology, Geological Survey of India, Central Region, Nagpur, India