1. Lecture Notes in Math.;J. Az�ma,1972
2. Az�ma, J.: ?Th�orie g�n�rale des processus et retournement du temps?,Ann. Sci. de l'Ecole Norm. Sup. 6 (1973), 459?519.
3. Baxter, J., Dal Maso, G., and Mosco, U.: ?Stopping times and ?-convergence?,Trans. Amer. Math. Soc. 303 (1987), 1?38.
4. Blumenthal, R. M. and Getoor, R. K.:Markov Processes and Potential Theory, Academic Press, New York, 1968.
5. Chung, K. L.:Lectures from Markov Processes to Brownian Motion, Springer-Verlag, Berlin, Heidelberg, New York, 1982.