Volume 134, Issue 3, November 1991

Hausdorff dimension of sets of nonergodic measured foliations

Pages 455-543 by Howard Masur, John Smillie

On Raghunathan’s measure conjecture

Pages 545-607 by Marina Ratner

The modulus of polynomials with zeros on the unit circle: A problem of Erdös

Pages 609-651 by József Beck

On the base space of a semi-universal deformation of rational quadruple points

Pages 653-678 by Theo de Jong, Duco van Straten