Constant volume exponential solutions in Einstein-Gauss-Bonnet flat   anisotropic cosmology with a perfect fluid
  In this paper we investigate the constant volume exponential solutions (i.e. the solutions with the scale factors change exponentially over time so that the comoving volume remains the same) in the Einstein-Gauss-Bonnet gravity. We find conditions for these solutions to exist and show that they are compatible with any perfect fluid with the equation of state parameter $\omega<1/3$ if the matter density of the Universe exceeds some critical value. We write down some exact solutions which generalize ones found in our previous paper for models with a cosmological constant. 
Dmitry Chirkov, Sergey A. Pavluchenko, Alexey Toporensky
gr-qc astro-ph.CO hep-th