Feynman integrals for non-smooth and rapidly growing potentials
  The Feynman integral for the Schroedinger propagator is constructed as a generalized function of white noise, for a linear space of potentials spanned by measures and Laplace transforms of measures, i.e., locally singular as well as rapidly growing at infinity. Remarkably, all these propagators admit a perturbation expansion. 
Margarida de Faria, Maria Joao Oliveira and Ludwig Streit