The method of Fe-57 nuclear magnetic resonance (NMR) has been used to
study the electron-nuclear interaction and spin reorientation in HoFeO
3. In the temperature range of 53 lo 62 K a violation of the magnetic
equivalence of Fe3+ ions has been found which is due to the spin-reori
entational phase transition GAMMA2 --> GAMMA4 . The experimental data
are compared with the results of other papers.