Magnetodielectric effect and spin state of iron ions in iron-substituted bismuth pyrostannate Lubov Udod, Sergey Aplesnin, Maxim Sitnikov, Oxana Romanova, Oleg Bayukov, Alexander Vorotinov, Dmitriy Velikanov and Gennadiy Patrin Eur. Phys. J. Plus, 135 10 (2020) 776 Published online: 06 October 2020 DOI: 10.1140/epjp/s13360-020-00781-2