On the influence of the lower order terms on the Gevrey local solvability of a class of equations with multiple characteristics.

In this paper, we are concerned with the local solvability of a class of semilinear partial differential equations that are, in general, not locally solvable in C ∞ . The linear part has multiple characteristics and it is the composition of p operators, each of them contains lower order terms. We shall analyze the influence of these terms on the local solvability in Gevrey classes. [ABSTRACT FROM AUTHOR]