2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/46785A general approach for evaluating the nonfactorizable contributions to the hadronic matrix elements is described in terms of the higher twist wave functions of the mesons. An example is illustrated for the $B^{0} \to π^{+}π^{-}$ decays.9 pages, Latex, no figuresHigh Energy Physics - Phenomenologytext