De Sitter solutions in N=4 matter coupled supergravity
  We investigate the scalar potential of gauged N=4 supergravity with matter. The extremum in the SU(1,1)/U(1) scalars is obtained for an arbitrary number of matter multiplets. The constraints on the matter scalars are solved in terms of an explicit parametrisation of an   SO(6,6+n) element. For the case of six matter multiplets we discuss both compact and noncompact gauge groups.   In an example involving noncompact groups and four scalars we find a potential with an absolute minimum and a positive cosmological constant. 
M. de Roo, D.B. Westra and S. Panda