J. P. Lees, V. Poireau, V. Tisserand, N. Arnaud, M. Davier, et al.. Observation of $\overline{B} \to D^{(*)} \pi^+\pi^- \ell^-\overline{\nu}$ decays in $e^+e^-$ collisions at the $\Upsilon(4S)$ resonance.
Physical Review Letters, American Physical Society, 2016, 116, pp.041801.
⟨10.1103/PhysRevLett.116.041801⟩.
⟨in2p3-01182326⟩