%0 Journal Article
%T PERIODIC SOLUTIONS OF CERTAIN THREE
DIMENSIONAL AUTONOMOUS SYSTEMS
%J Journal of Sciences, Islamic Republic of Iran
%I University of Tehran
%Z 1016-1104
%D 1999
%\ 06/01/1999
%V 10
%N 2
%P -
%! PERIODIC SOLUTIONS OF CERTAIN THREE
DIMENSIONAL AUTONOMOUS SYSTEMS
%R
%X There has been extensive work on the existence of periodic solutions for nonlinear
second order autonomous differantial equations, but little work regarding the third
order problems. The popular Poincare-Bendixon theorem applies well to the former
but not the latter (see [2] and [3]). We give a necessary condition for the existence of
periodic solutions for the third order autonomous systems, This may become useful
in further investigations. Our claims are proved and supported by certain examples.
%U https://jsciences.ut.ac.ir/article_31492_4c876434368592fefa4f89f39e5bc3b9.pdf