Four-Quark Mesons in Non-leptonic B Decays--Could They Resolve Some Old   Puzzles?
  We point out that non-leptonic B decays driven by b-->ccbar s should provide a favourable environment for the production of hidden charm diquark-antidiquark bound states that have been suggested to explain the resonances with masses around 4 GeV recently observed by BaBar and BELLE. Studying their relative abundances in non-leptonic B decays can teach us novel lessons about their structure and the strong interactions. Through their decay into psi they can provide a natural explanation of the excess of B-->psi X observed for p_psi < 1 GeV. Other phenomenological consequences are mentioned as well. 
I. Bigi, L. Maiani, F. Piccinini, A.D. Polosa, V. Riquer