TEJ BAHADUR SINGH is an Emeritus Professor at the Department of Mathematics, University of Delhi, India, which he joined in 1989. Earlier, he served at the University of Allahabad and Atarra P.G. College, Banda, India. He received his Ph.D. from the University of Allahabad in 1983. With more than 40 years of teaching experience, he has written several research articles on the cohomological theory of compact transformation groups and has successfully guided eight M.Phil. and Ph.D. students. His primary research interest is in algebraic topology. He has taught various courses, including point-set topology, field theory, module theory, representation of finite groups, algebra, calculus, geometry, linear algebra, and real analysis.