Experimental observations are reported of the splitting of NMR lines of Fe-
57 into two absorption peaks in a static magnetic field H-0 parallel to a v
ariable field H-1 in the basis plane. The field dependence of the intensity
and the variation in the resonance frequencies of the absorption peaks wit
h H-0 are studied. These results can be used to explain some features of th
e layered domain structure of iron borate. (C) 1999 American Institute of P
hysics. [S1063-7834(99)01902-4].