  An elastic anomaly, observed in the heavy Fermi liquid state of Ce alloys
(for example, CeCu_6 and CeTe), is analyzed by using the infinite-U Anderson
lattice model. Four atomic energy levels are assumed for f-electrons. Two of
them are mutually degenerate. A small crystalline splitting 2 Delta is assumed
between two energy levels. Fourfold degenerate conduction bands are also
considered. We solve the model using the mean field approximation to slave
bosons and the renormalized elastic constant is calculated. The temperature
dependence of the constant shows the downward dip. The result is compared with
the experimental data of CeTe.
