Function-Space Differential Equations Associated with a Stochastic Partial Differential Equation Pao-Liu Chow Indiana University Mathematics Journal 1976 text pdf 10.1512/iumj.1976.25.25049 10.1512/iumj.1976.25.25049 en Indiana Univ. Math. J. 25 (1976) 609 - 627 state-of-the-art mathematics http://iumj.org/access/