“The Boltzmann distribution and molecular gases” explains why an “ordinary” gas has its molecules Boltzmann-distributed. The most concentrated Fermi–Dirac gas, helium 3 at its boiling point, is still in a “dilute limit”, dilute enough to be approximately Boltzmann. Similarly, the most concentrated Bose–Einstein gas, helium 4 at its boiling point, is also approximately Boltzmann.
Controlling the Phase Transition in Superfluid Helium-3