In this paper the periodic solutions of fourth order delay differential equation of the form $\ddddot{x}(t)+a\dddot{x}(t)+f(\ddot{x}(t-\tau(t)))+g(\dot{x}(t-\tau(t)))+h({x}(t-\tau(t)))=p(t)$ is investigated. Some new positive periodic criteria are given.
Balamuralitharan, S. (2015). Periodic solutions of fourth-order delay differential equation. Bulletin of the Iranian Mathematical Society, 41(2), 307-314.
MLA
S. Balamuralitharan. "Periodic solutions of fourth-order delay differential equation". Bulletin of the Iranian Mathematical Society, 41, 2, 2015, 307-314.
HARVARD
Balamuralitharan, S. (2015). 'Periodic solutions of fourth-order delay differential equation', Bulletin of the Iranian Mathematical Society, 41(2), pp. 307-314.
VANCOUVER
Balamuralitharan, S. Periodic solutions of fourth-order delay differential equation. Bulletin of the Iranian Mathematical Society, 2015; 41(2): 307-314.