We consider flame front propagation in channel geometries. The steady-state
solution in this problem is space dependent and therefore the linear stabi
lity analysis is described by a partial integro-differential equation with
a space-dependent coefficient. Accordingly. it involves complicated eigenfu
nctions. We show that the analysis can be performed using a finite-order dy
namical system in terms of the dynamics of singularities in the complex pla
ne, yielding a detailed understanding of the physics of the eigenfunctions
and eigenvalues. [S1063-651X(99)01902-9].