PageHeader : Funkcialaj Ekvacioj, 16 (1973) 169-180 Title : An Analytical Method for Certain Highly Title : Nonlinear Periodic Differential Equations AuthorInfo : By Rene VAN DOOREN AuthorInfo : (Free University of Brussels) section : 1. Introduction. section : 2. The first improved approximation. section : 3. The second improved approximation. section : 4. The higher improved approximations. section : 5. The error in the equation. section : 6. An application of our method. section : Acknowledgement. section : References