Electronic Journal of Differential Equations,
Conference 07 (2001), pp. 99-102.

Title: Almost periodic solutions of nonlinear hyperbolic equations with
  time delay.

Authors: Hushang Poorkarimi (Univ. of Texas-Pan American, Edinburg, TX, USA)
  Joseph Wiener (Univ. of Texas-Pan American, Edinburg, TX, USA)

 Abstract: 
  The almost periodicity of bounded solutions is established for a nonlinear
  hyperbolic equation with piecewise continuous time delay. The equation
  represents a mathematical model for the dynamics of gas absorption.

Published July 20, 2001.
Math Subject Classifications: 35B10, 35B15, 35J60, 35L70.
Key Words: Nonlinear hyperbolic equation; time delay; 
  almost periodic solution.