  In [5] and [19], the authors gave anomaly cancellation formulas for the gauge
groups E8,E8*E8. In this paper, we mainly deal with the case of gauge group
E8*E8*E8. Using the E8*E8*E8 bundle, we construct some modular forms over
SL2(Z). By these modular forms, we get some new anomaly cancellation formulas
of characteristic forms.
