  Perturbations commonly added to the KdV equation contain terms that represent
inelastic interac-tions among KdV solitons in multiple-soliton solutions. These
terms trigger the emergence of new waves in the first-order correction to the
solution of the perturbed equation. The new waves can represent
soliton-anti-soliton creation, annihilation and scattering. Other possible
waves represent soliton decay and production.
