Mathematics Department, Science and Arts Faculty, Mersin University, 33343 Mersin, Turkey
Academic Editor: I. T. Kiguradze
Copyright © 2010 Hamza Menken. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
In the present paper, we consider a nonself-adjoint fourth-order
differential operator with the periodic boundary conditions. We compute new accurate asymptotic expression of the fundamental solutions of the given equation. Then, we obtain new accurate asymptotic formulas for eigenvalues and eigenfunctions.