  We demonstrate that, in contrast with what was previously believed,
multi-hump solitary waves can be stable. By means of linear stability analysis
and numerical simulations, we investigate the stability of two- and three-hump
solitary waves governed by incoherent beam interaction in a saturable medium,
providing a theoretical background for the experimental results reported by M.
Mitchell, M. Segev, and D. Christodoulides [Phys. Rev. Lett. v. 80, p. 4657
(1998)].
