1. References to the early work on 3He-4He dilution refigeration can be found in [7.8, 9]
2. G. Frossati: J. de Phys. 39(C6), 1578 (1978); J. Low Temp. Phys. (to be published 1992 )
3. G.A. Vermeulen, G. Frossati: Cryogenics 27, 139 (1987)
4. J.C. Wheatley: Am. J. Phys. 36, 181 (1968); and in Progress in Low Temperature Physics, Vol.6, ed. by C.J. Gorter ( North-Holland, Amsterdam 1970 ) p. 77
5. J.C. Wheatley, O.E. Vilches, W.R. Abel: Physics 4, 1 (1968)