Prof. John R. Graef is a Professor of Mathematics in the Department of Mathematics at the University of Tennessee at Chattanooga. He earned his Ph.D. in Mathematics from Southern Illinois University in Carbondale in 1970. As of 2021, he has authored 500 papers in various academic journals. His research interests span ordinary and functional differential equations, difference equations, impulsive systems, differential inclusions, fractional differential equations, and dynamic equations on time scales, with applications in diverse fields. His special research focuses include nonlinear oscillations—particularly stability, oscillation, nonoscillation, and other asymptotic solution properties for nonlinear equations—alongside boundary value problems, contol trheory, dynamical systems, variational methods, and mathematical modeling.