The evolution of the eigenfunctions in the Lax representation of the KdV hi
erarchy with self-consistent sources possesses singularity. By proposing a
method to treat the singularity to determine the evolution of scattering da
ta, the KdV hierarchy with self-consistent sources is integrated by the inv
erse scattering method. The soliton solutions of these equations are obtain
ed. It is shown that the insertion of a source may cause the variation of t
he speed of soliton. This approach can be applied to other (1 + 1)-dimensio
nal soliton hierarchies. (C) 2001 Elsevier Science B.V. All rights reserved
.