SH, Z. . H. and S, F.F. 2011. VARIATIONAL FORMULATION OF NONLINEAR ORDINARY DELAY DIFFERENTIAL EQUATIONS. Journal of Al-Qadisiyah for Computer Science and Mathematics. 3, 1 (Feb. 2011), Math Page 314– 325. DOI:https://doi.org/10.29304/jqcm.2011.3.1.703.