Comment on “A generalized Langevin formalism of complete DNA melting transition” by Das T. and Chakraborty S.T. S. van Erp, S. Cuesta-Lopez, J.-G. Hagmann and M. PeyrardEPL, 85 6 (2009) 68003DOI: https://doi.org/10.1209/0295-5075/85/68003