Kernel estimates for nonautonomous Kolmogorov equations with potential   term
  Using time dependent Lyapunov functions, we prove pointwise upper bounds for the heat kernels of some nonautonomous Kolmogorov operators with possibly unbounded drift and diffusion coefficients and a possibly unbounded potential term. 
Markus Kunze, Luca Lorenzi and Abdelaziz Rhandi
math.AP