  In the present paper, we are considering a spatially-flat
Friedmann-Robertson-Walker cosmological model, fueled with stiff matter and
dust, treated as non-interacting ideal fluid sources. By solving the
corresponding Friedmann equation with a non-zero cosmological constant, we are
deriving the scale function and the fundamental cosmological parameters. Within
a thermodynamic approach, the general form of the Equation of State is
obtained, together with the explicit dependence of the energy density and
pressure on temperature.
