Abstract:
The equivalence of the notion of a regular boundary point with that of a quasi regular boundary point is proved in this paper for a wide class of Markov processes in a semicompact. The criterion for a point to be regular which is analogous to the criterion of Valle-Poussin (in the theory of differential equations) is used to prove that when certain conditions are satisfied a point is regular for one process if and only if it is regular for another one.