1. P. A. Bottomley, NMR imaging techniques and applications, Rev. Sci. Instrum. 53 (9): 1319 (1982).
2. T. F. Budinger and P. C. Lauterbur, Nuclear magnetic resonance technology for medical studies, Science, 226:288 (1984),.
3. F. F. Murray, K. F. Hwang and W. D. Markiewicz, Refrigerator operating experience on whole body MRI magnet systems, in: “Advances in Cryogenic Engineering,” Vol. 31, Plenum Press, New York (1986).
4. R. C. Longsworth, Interfacing small closed cycle refriderators to liquid helium cryostats, Cryogenics, 24: 175 (1984).
5. R. C. Longsworth, 4 K refrigerator and interface for MRI cryostats, in: “Advances in Cryogenic Engineering,” Vol. 31, Plenum Press, New York (1986).