%0 Journal Article %T Hyers-Ulam stability of functional equations in 2-Banach spaces %A Sang-Cho Chung %A Won-Gil Park %J International Journal of Mathematical Analysis %D 2012 %I %U http://www.m-hikari.com/ijma/ijma-2012/ijma-17-20-2012/parkwongilIJMA17-20-2012.pdf