Determination of the anisotropy fields of polycrystalline hexaferrites by FMR Victor A. Zhuravlev, Alexander V. Zhuravlev, Vasily V. Atamasov and Grigory I. Malenko ITM Web Conf., 30 (2019) 07007 Published online: 27 November 2019 DOI: 10.1051/itmconf/20193007007