Higher Integrability from Reverse Holder Inequalities E. Stredulinsky Indiana University Mathematics Journal 1980 text pdf 10.1512/iumj.1980.29.29029 10.1512/iumj.1980.29.29029 en Indiana Univ. Math. J. 29 (1980) 407 - 413 state-of-the-art mathematics http://iumj.org/access/