Electronic Journal of Differential Equations,
Vol. 2007(2007), No. 62, pp. 1-5.

Title: Forced oscillations for delay motion equations on manifolds

Authors: Pierluigi Benevieri (Univ. degli Studi di Firenze, Italy)
         Alessandro Calamai  (Univ. Politecnica delle Marche, Italy)
         Massimo Furi        (Univ. degli Studi di Firenze, Italy)
	 Maria Patrizia Pera (Univ. degli Studi di Firenze, Italy)  

Abstract:
 We prove an existence result for $T$-periodic solutions of a
 $T$-periodic second order delay differential equation on a
 boundaryless compact manifold with nonzero Euler-Poincare
 characteristic. The approach is based on an existence result
 recently obtained by the authors for first order delay differential
 equations on compact manifolds with boundary.
  
Submitted July 29, 2006. Published April 26, 2007.
Math Subject Classifications: 34K13, 37C25.
Key Words: Delay differential equations; Forced oscillations;
           periodic solutions; compact manifolds; 
	   Euler-Poincare characteristic; fixed point index.