Local Smoothing Properties of Schroedinger Equations Peter ConstantinJ. Saut Indiana University Mathematics Journal 1989 text pdf 10.1512/iumj.1989.38.38037 10.1512/iumj.1989.38.38037 en Indiana Univ. Math. J. 38 (1989) 791 - 810 state-of-the-art mathematics http://iumj.org/access/