Dr. Harendra Singh is an Assistant Professor in the Department of Mathematics at Post-Graduate College Ghazipur, Uttar Pradesh, India. He teaches post-graduate mathematics courses including Real and Complex Analysis, Functional Analysis, Abstract Algebra, and Measure Theory. His research areas of interest include Mathematical Modelling, Fractional Differential Equations, Integral Equations, Calculus of Variations, and Analytical and Numerical Methods. He is the co-Editor with Dr. Srivastava of Special Functions in Fractional Calculus and Engineering, Taylor and Francis/CRC Press.