  Ground state ferromagnetism of the Kondo lattices is investigated within
slave fermion approach by Coleman and Andrei within a mean-field approximation
in the effective hybridization model. Conditions for formation of both
saturated (half-metallic) and non-saturated magnetic state are obtained for
various lattices. A description in terms of universal functions which depend
only on bare electron density of states (DOS) is presented. A crucial role of
the energy dependence of the bare DOS (especially, of DOS peaks) for the
small-moment ferromagnetism formation is demonstrated.
