Electronic Journal of Differential Equations,
Conference 05 (2000), pp. 113-119.

Title: A Second look at the first result of Landesman-Lazer type.

Authors: Alan C. Lazer (Univ. of Miami, Coral Gables, FL, USA)
 
Abstract: 
  We discuss some results concerning periodic and almot periodic solutions
  of ordinary differential equations which are precursors of a result on
  weak solutions of a semilinear elliptic boundary due to E. M. Landesman
  and the author. It is observed that in the earliest of these, if one 
  looks for periodic solutions instead of almost peridic solutions,
  then the conditions can be relaxed.

Published October 24, 2000.
Math Subject Classifications: 34C25, 34C27.
Key Words: Globally asymptotically stable; Brouwer fix-point theorem;
  polar coordinates.