The neutron and proton mass radii from the vector meson photoproduction data on the deuterium target Chengdong Han, Gang Xie, Wei Kou, Rong Wang and Xurong Chen Eur. Phys. J. A, 58 6 (2022) 105 Published online: 08 June 2022 DOI: 10.1140/epja/s10050-022-00756-0