1. , and VI. Internat. Conf. Physics and Techniques of Low Temperatures in Socialistic Countries, Wrocław 1967;
2. XX. Congr. of Polish Physicists, Lublin 1967.
3. , , and VIII. Internat. Conf. Physics and Techniques of Low Temperatures in Socialistic Countries, Dresden 1969.
4. Proc. VIII. Conf. Thermal Conductivity, Plenum Press, New York 1969 (p. 373).