%0 Journal Article %T Stability of a Mixed Type Additive, Quadratic,Cubic and Quartic Functional Equation %A M. Eshaghi-Gordji %A S. Kaboli-Gharetapeh %A Sal Moslehian, Mohammad %A S. Zolfaghari %J Nonlinear Analysis and Variational Problems %@ 1931-6828 %D 2010