%0 Journal Article %T Positive solutions for a coupled system of nonlinear differential equations of mixed fractional orders %A Zhao Yige %A Sun Shurong %A Han Zhenlai %A Feng Wenquan %J Advances in Difference Equations %D 2011 %I Springer %X In this article, we study the existence of positive solutions for a coupled system of nonlinear differential equations of mixed fractional orders where 2 < ¦Á ¡Ü 3, 3 < ¦Â ¡Ü 4, , are the standard Riemann-Liouville fractional derivative, and f, g : [0, 1] ¡Á [0, +¡Þ) ¡ú [0, +¡Þ) are given continuous functions, f(t, 0) ¡Ô 0, g(t, 0) ¡Ô 0. Our analysis relies on fixed point theorems on cones. Some sufficient conditions for the existence of at least one or two positive solutions for the boundary value problem are established. As an application, examples are presented to illustrate the main results. %K Positive solution %K coupled system %K fractional Green's function %K fixed point theorem %U http://www.advancesindifferenceequations.com/content/2011/1/10