Cosmological solutions with massive gravitons
  We present solutions describing spatially closed, open, or flat cosmologies in the massive gravity theory within the recently proposed tetrad formulation. We find that the effect of the graviton mass is equivalent to introducing to the Einstein equations a matter source that can consist of several different matter types -- a cosmological term, quintessence, gas of cosmic strings, and non-relativistic cold matter. 
Ali H. Chamseddine and Mikhail S. Volkov
hep-th