Eigenfunctions of $GL(N,\RR)$ Toda chain: The Mellin-Barnes   representation
  The recurrent relations between the eigenfunctions for $GL(N,\RR)$ and $GL(N-1,\RR)$ quantum Toda chains is derived. As a corollary, the Mellin-Barnes integral representation for the eigenfunctions of a quantum open Toda chain is constructed for the $N$-particle case. 
S. Kharchev, D. Lebedev