  We consider a generalization of the three spectral inverse problem, that is,
for given spectrum of the Dirichlet-Dirichlet problem (the Sturm-Liouville
problem with Dirichlet conditions at both ends) on the whole interval $[0,a]$,
parts of spectra of the Dirichlet-Neumann and Dirichlet-Dirichlet problems on
$[0,a/2]$ and parts of spectra of the Dirichlet-Newman and Dirichlet-Dirichlet
problems on $[a/2,a]$, we find the potential of the Sturm-Liouville equation.
