Yudi, X., M. Xingkui, L. Mao, Z. Zhe, and M. A. E. Andersen. “Analysis and Optimization of Coupled Windings in Magnetic Resonant Wireless Power Transfer Systems With Orthogonal Experiment Method”. Elektronika Ir Elektrotechnika, vol. 23, no. 6, Dec. 2017, pp. 34-39, doi:10.5755/j01.eie.23.6.19692.