Functions of a Markov Process That are Markovian Murray Rosenblatt Indiana University Mathematics Journal 1959 text pdf 10.1512/iumj.1959.8.58039 10.1512/iumj.1959.8.58039 en Indiana Univ. Math. J. 8 (1959) 585 - 596 state-of-the-art mathematics http://iumj.org/access/