An Extension of the Law of the Iterated Logarithm to Variables without Variance William Feller Indiana University Mathematics Journal 1969 text pdf 10.1512/iumj.1969.18.18027 10.1512/iumj.1969.18.18027 en Indiana Univ. Math. J. 18 (1969) 343 - 355 state-of-the-art mathematics http://iumj.org/access/