Crossed product decompositions of a purely infinite von Neumann algebra with faithful, almost periodic weight Kenneth Dykema Indiana University Mathematics Journal 1995 text pdf 10.1512/iumj.1995.44.1995 10.1512/iumj.1995.44.1995 en Indiana Univ. Math. J. 44 (1995) 433 - 450 state-of-the-art mathematics http://iumj.org/access/