  The susceptibility of an overdamped Markov system fluctuating in a bistable
potential of general form is obtained by analytic solution of the Fokker-Planck
equation (FPE) for low noise intensities. The results are discussed in the
context of the LRT theory of stochastic resonance. They go over into recent
results (Gang Hu et al {\em Phys. Lett. A} {\bf 172}, 21, 1992) obtained from
the FPE for the case of a symmetrical potential, and they coincide with the LRT
results (Dykman et al, {\em Phys. Rev. Lett.} {\bf 65}, 2606, 1990; {\em JETP
Lett} {\bf 52}, 144, 1990; {\em Phys. Rev. Lett.} {\bf 68}, 2985, 1992)
obtained for the general case of bistable systems.
