1977
Kneppo, I. and Weis, M.: Measurement of mictowave loss tangent by means of microwave resonator bridge, IEEE MTT 25 (1977) 418.
1978
Watanabe, K., Kneppo, I., and Weiss, M.: Commnets on Measurements of microwave loss tangent by means of microwave resonator bridge, IEEE MTT 26 (1978) 314.