Comment on Singularity-free Cosmological Solutions with Non-rotating   Perfect Fluids
  A conjecture stated by Raychaudhuri which claims that the only physical perfect fluid non-rotating non-singular cosmological models are comprised in the Ruiz-Senovilla and Fernandez-Jambrina families is shown to be incorrect. An explicit counterexample is provided and the failure of the argument leading to the result is explicitly pointed out. 
L. Fernandez-Jambrina