Dheeraj Kumar is a Research Scholar at Mining Department, Indian Institute of Technology at Kharagpur, India, where he conducts research in rock mechanics. D. Kumar can be accessed by email.

P. K. Behera is the Deputy Director of National Institute of Rock Mechanics, Champion Reef, KGF, Banglore, India.

U. K. Singh is a Professor at Mining Engineering Department, Indian School of Mines, Dhanbad, India.