Modelling Late Oligocene C4 grasses and climate Lunt, Daniel J. ; Ross, Ian ; Hopley, Philip J. ; Valdes, Paul J. Abstract Publication: Palaeogeography Palaeoclimatology Palaeoecology Pub Date: August 2007 DOI: 10.1016/j.palaeo.2007.04.004 Bibcode: 2007PPP...251..239L