Schnabl's Solution and Boundary States in Open String Field Theory
  We discuss that Schnabl's solution is an off-shell extension of the boundary state describing a D-brane in the closed string sector. It gives the physical meaning of the gauge invariant overlaps for the solution in our previous paper and supports Ellwood's recent proposal in the operator formalism. 
Teruhiko Kawano, Isao Kishimoto, Tomohiko Takahashi