RamRakhyani, A.K.; Lazzi, G.: 'Interference-free wireless power transfer system for biomedical implants using multi-coil approach', Electronics Letters, 2014, 50, (12), p. 853-855, DOI: 10.1049/el.2014.0567 IET Digital Library, https://digital-library.theiet.org/;jsessionid=2kxqojyvibvvn.x-iet-live-01content/journals/10.1049/el.2014.0567