“…(1.2) Equation (1.1) models heat transfer in a medium where the thermal conductivity, convective transport, and sources or sinks of thermal energy may depend on the temperature but not on the place or time [4,5,38,109,113,146,147]. The equation also arises in various guises in numerous other fields [4,5,37,38,50,113] soil physics [19,33,74,128,137], population genetics [44,53,56,83,84,110,111,114], fluid dynamics [25, 28 30], neurology [53,112,132], combustion theory [20,26,27,144] and reaction chemistry [7,8,53], to name but a few. In these situations, the second-order term on the right-hand side of (1.1) describes a diffusive process, the first-order term corresponds to a convective or advective process, and the zero-order term is associated with reaction, sorption, sources or sinks.…”