  Attention is drawn to the observation that in many correlated systems (e.g.
3He, heavy fermion systems and Hubbard models) the specific heat curves, when
plotted for different values of some thermodynamic variable (e.g. pressure,
magnetic field, interaction), cross almost precisely at one or two
characteristic temperatures. A quantitative explanation of this phenomenon,
based on the temperature dependence of the associated generalized
susceptibilities, is presented.
