Volume 113, Issue 1 – January 1981

## The existence of minimal immersions of $2$-spheres

Pages 1-24 by Jonathan Sacks, Karen Uhlenbeck

## Negative solutions to Post’s problem. II

Pages 25-43 by Sy-David Friedman

## Degeneration of surfaces with trivial canonical bundle

Pages 45-66 by Ulf Persson, Henry Pinkham

## Kohn-Rossi cohomology and its application to the complex Plateau problem. I

Pages 67-110 by Stephen S.-T. Yau

## Arithmetic properties of power series solutions of algebraic differential equations

Pages 111-157 by Yasutaka Sibuya, Steven Sperber

## Bernoulli diffeomorphisms and group extensions of dynamical systems with non-zero characteristic exponents

Pages 159-179 by Michael Brin, Jacob Feldman, Anatole Katok

## $K$-theory for certain $C^\ast$-algebras

Pages 181-197 by Joachim Cuntz

## On Novikov’s conjecture for non-positively curved manifolds. I

Pages 199-209 by F. Thomas Farrell, Wu Chung Hsiang

## The Gauss map of a complete non-flat minimal surface cannot omit $7$ points of the sphere

Pages 211-214 by Frederico Xavier