%0 Journal Article %T ON THE PERIODIC SOLUTIONS OF A CLASS OF nTH ORDER NONLINEAR DIFFERENTIAL EQUATIONS * %J Journal of Sciences, Islamic Republic of Iran %I University of Tehran %Z 1016-1104 %D 1998 %\ 03/01/1998 %V 9 %N 1 %P - %! ON THE PERIODIC SOLUTIONS OF A CLASS OF nTH ORDER NONLINEAR DIFFERENTIAL EQUATIONS * %R %X The nth order differential equation x + c (t )x + ƒ( t,x) = e(t),n>3 is considered. Using the Leray-Schauder principle, it is shown that under certain conditions on the functions involved, this equation possesses a periodic solution. %U https://jsciences.ut.ac.ir/article_31366_8c8d837537a008e02f3aa01625724fb6.pdf