Comments on "Plasma oscillations and nonextensive statistics"
  The paper, authored by J. A. S. Lima et al, was published in Phys. Rev. E in 2000 has discussed the dispersion relation and Landau damping of Langmuir wave in the context of the nonextensive statistics proposed by Tsallis. It has been cited by many authors because the dispersion relation in Tsallis formalism present a good fit to the experimental data when q<1, while the classical result based on Maxwellian distribution only provides a crude description. However, the results obtained in this paper are problematic. In this comments on the paper we shall derive the correct analytic formulas both for the dispersion relation and Landau damping in Tsallis formalism. We hope that this comments will be useful in providing the correct results. 
Xiao-Chang Chen and X.Q.Li
physics.plasm-ph