Helium-three
https://en.wikipedia.org/wiki/Liquid_helium
$\rho_{He^3} = (1/8) \rho_{water} \approx 0.12 g/cm^3$
https://en.wikipedia.org/wiki/Liquid_helium
http://ltl.tkk.fi/research/theory/helium.html
http://fy.chalmers.se/~delsing/LowTemp/LectureNotes/LectureNotes13.PDF
1992 specific heat of He-3
Fermi energy https://en.wikipedia.org/wiki/Fermi_energy
https://onlinelibrary.wiley.com/doi/pdf/10.1002/phbl.19760321214
$T_F = 1.5 K$
superfluid transitions The extraordinary phases of liquid 3-He - David M. Lee
http://fy.chalmers.se/~delsing/LowTemp/LectureNotes/LectureNotes13.PDF
- specific heat
1973 Observation of a Second-Order Phase Transition and Its Associated Phase Diagram in Liquid He3 R. A. Webb, T. J. Greytak, R. T. Johnson, and J. C. Wheatley