Remarks on the general solution for the flat Friedman universe with   exponential scalar-field potential and dust
  We show that the simple extension of the method of obtaining the general exact solution for the cosmological model with the exponential scalar-field potential to the case when the dust is present fails and we discuss the reasons of this puzzling phenomenon. 
A.A. Andrianov, F. Cannata, A.Y. Kamenshchik
gr-qc