Hartmut Logemann is a Professor in the Department of Mathematical Sciences, University of Bath, UK. He has taught a large variety of topics, including courses in complex analysis, control theory, engineering mathematics, Lyapunov theory, ordinary differential equations and semigroups of linear operators. His research interests are in mathematical systems and control theory with emphasis on infinite-dimensional systems, nonlinearity, positivity and sampled-data control.Eugene P. Ryan is Professor Emeritus in the Department of Mathematical Sciences, University of Bath, UK. He has lectured on a wide variety of topics to diverse audiences at both undergraduate and postgraduate levels, including courses on abstract analysis, control theory, nonsmooth optimization, ordinary differential equations, and mathematical methods for engineers & scientists. His research interests lie in mathematical systems and control theory, with emphasis on stabilization and optimization of nonlinear systems.