Quasi-equilibrium nonadditivity
  The possibility that a short-range interacting system exhibits nonadditivity is investigated. After the discussion on the precise definition of additivity and its consequence, we show that it is possible when the system is in a quasi-equilibrium state by examining the specific model, in which the spin degrees of freedom are coupled to the motional degrees of freedom and which exhibits a type of structural phase transitions. 
Takashi Mori
cond-mat.stat-mech