World Volume Action for Fractional Branes
  We study the world volume action of fractional Dp-branes of type IIA string theory compactified on the orbifold T^4/Z_2. The geometric relation between these branes and wrapped branes is investigated using conformal techniques. In particular we examine in detail various scattering amplitudes and find that the leading low-energy interactions are consistent with the boundary action derived geometrically. 
P. Merlatti and G. Sabella