1. J. Bánkuti, I. Kirschner, L. Lászlóffy and J. Lukács, Proc. 6th Magnet Techn. Conf., p. 390., Bratislava, 1977.
2. G. Fricsovszky, I. Kirschner, I. Kovács and E. Papp, Proc. 3rd Intern. Cryogenic Eng. Conf., p. 362., West-Berlin, 1970.
3. I. Kirschner, I. Kovács and L. Lászlóffy, Proc. 4th Intern. Cryogenic Eng. Conf., p. 372., Eindhoven, 1972.
4. I. Kirschner, T. Porjesz and G. Reményi, Cryogenics,17, 565, 1977.
5. D. Atherton, Canad. J. Phys.,47, 753, 1969.