1. Pond R., Maddin R.: Trans. AIME256 (1969) 2475;
2. Chen S., Miller C. E.: Rev. Sci. Instrum.41 (1970) 1237.
3. Older experimental results were reviewed in Závěta K., Schneider J.:in Proc. of the Conf. Amorph. Met. Mat., Veda, Bratislava, 1980, p. 367.
4. Egami T., Flanders P. J.: APS Conf. Proc. No. 29 (1976) p. 220.
5. Hilzinger H. R.:in Proc. 4th Int. Conf. RQM, Sendai, 1981, p. 791.