1. Yu. V. Gulyaev, S. V. Gerus, V. D. Zhitkovskii, et al., Inzh. Fiz., No. 2, 2 (2004).
2. Yu. V. Gulyaev, S. V. Gerus, A. N. Zelenin, et al., RF Patent No. 35920, Byull. Izobret., No. 4 (2004).
3. Yu. V. Gulyaev, B. S. Lobanov, A. Yu. Mityagin, and B. V. Khlopov, Inzh. Fiz., No. 1, 36 (2010).
4. A. G. Roy, S. Jeong, and D. E. Laughlin, IEEE Trans. Magn. 38, 2018 (2002).