The effects of Mn-substitutions in the Y2Fe17 and Er2Fe17 compounds have been studied by
magnetization measurements. The magnetic moment and the magnetic anisotropy of the 3d sublattice are
found to reduce upon increasing the Mn-concentration. The magnetization reorientation processes that exist
in the Er2Fe14Mn3 and Er2Fe13Mn4 compounds are, therefore, a consequence of competing contributions
of the planar anisotropy of the 3d sublattice and the axial one of the erbium partner. ?? 1988.
