1. T. T. Rule and E. B. Qvale, in: Advances in Cryogenic Engineering, Vol, 14, Springer Science+Business Media New York (1969), p. 343.
2. A. Sherman, “Mathematical Analysis of a Vuilleumier Refrigerator,” paper No. 71-WA/HT-33 presented at ASME 1971 Winter Annual Meeting, Los Angeles, California, November 1971.
3. M. Gasser, D. Yoshikawa, and C. Browning, “An Approach to Long Life Vuilleumier Cryogenic Refrigerators for Space Applications,” paper presented at the Cryogenic Society of America, Washington, D.C., September 1971.
4. A. Sherman and T. Cygnanowicz, “Design Scaling Studies of Fractional Watt Vuilleumier Refrigerator Systems,” GSFC X–763–71–447, NASA Goddard Space Flight Center, Greenbelt, Maryland (1971).