%0 Journal Article %T Regularity for Solutions of Second-Order Nonlinear Integrodifferential Functional Equations %A Dong-Gun Park %A Jin-Mun Jeong %A Han-Geul Kim %J Journal of Inequalities and Applications %D 2010 %I Springer %R 10.1155/2010/280463 %X We deal with the well-posedness for solutions of nonlinear integrodifferential equations of second-order in Hilbert spaces by converting the problem into the contraction mapping principle with more general conditions on the principal operators and the nonlinear terms and obtain a variation of constant formula of solutions of the given nonlinear equations. %U http://dx.doi.org/10.1155/2010/280463