QUDDUS KHAN, PhD, is Senior Assistant Professor in the Department of Mathematics, Shibil National Postgraduate College, Azamgarh (UP). He has been teaching undergraduate and postgraduate classes for the last eight years. Earlier, he worked as a Young Scientist in the Department of Mathematics, Faculty of Natural Sciences, Jamia Millia Islamia (JMI), New Delhi and also as a Guest Lecturer in the Department of Applied Sciences, Faculty of Engineering, JMI, New Delhi. Dr. Khan has to his credit 14 research papers on Differentiable Manifolds published in various national and international journals, and has coauthored several books.