Electronic Journal of Differential Equations,
Vol. 2002(2002), No. 31, pp. 1-18.

Title: Differential equations with several deviating arguments:
       Sturmian comparison method in oscillation theory, II
   
Authors: Leonid Berezansky (Ben-Gurion Univ. of the Negev, Israel)
  Yury Domshlak (Ben-Gurion Univ. of the Negev, Israel)

Abstract: 
  We study the oscillation of solutions to the differential
  equation
  $$
  \dot{x}(t) +a_1(t)x[r(t)]+a_2(t)x[p(t)]=0, \quad t\geq t_0
  $$
  which has a retarded argument $r(t)$ and an advanced argument 
  $p(t)$. We obtain oscillation and non-oscillation conditions 
  which are closed to be necessary. We provide examples to show 
  that our results are best possible and compare them with 
  known results.
 
 
Submitted November 29, 2001. Published April 1, 2002.
Math Subject Classifications: 34K11.
Key Words: mixed differential equations, oscillation, 
           non-oscillation,  Sturmian comparison method.
  
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