An Effective Lagrangian with Broken Scale and Chiral Symmetry III:   Mesons at Finite Temperature
  We investigate the finite temperature behavior of the meson sector of an effective Lagrangian which describes nuclear matter. A method is developed for evaluating the logarithmic terms in the effective potential which involves expansion and resummation; the result is written in terms of the exponential integral. In the absence of explicit chiral symmetry breaking, a phase transition restores the symmetry at a temperature of 190 MeV; when the pion has a mass the transition is smooth. At a much higher temperature a first order phase transition restores scale symmetry. 
G.W. Carter, P.J. Ellis and S. Rudaz (University of Minnesota)