Compressible bag model and the phase structure
  The phase structure of hadrons and quark-gluon plasma is investigated by two types of equation of hadron state, namely ideal hadron gas model and the compressible bag model. It is pointed out that, while the ideal gas model produces unrealistic extra hadron phase, the compressible bag model gives an expected and reasonable phase diagram even if rich hadron spectrum is taken into account. 
Shigenori Kagiyama, Shunichiro Kumamoto, Akira Minaka, Akihiro   Nakamura, Kazunari Ohkura and Shogo Yamaguchi