It is shown that the linearization principle is true for a class of nonline
ar hyperbolic systems with two independent variables, time and space. To ke
ep clear exposition, our proof is based on the Saint Venant equation. More
results can be proven by using the Lyapunov function candidate that we give
here. (C) 2001 Academie des sciences/Editions scientifiques et medicales E
lsevier SAS.