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59:744 (1959).
2. J. Bourrat, private communication.
3. D. Mugnier and L. Weil, in: Advances in Cryogenic Engineering, Vol. 9, Plenum Press, New York (1964), p. 98.
4. C. J. Guntner and R. P. Reed, in: Advances in Cryogenic Engineerings Vol. 6, Plenum Press, New York (1961), p. 565; Vol. 7, Plenum Press, New York (1962), p. 500; Trans. ASM
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5. J. Bourrat and J. Hochmann, Soc. Française de Métallurgie, Journée des Aciers Spéciaux, Grenoble (June 1963).