Observation of decays B0-->Ds(*)+ pi- and B0-->Ds(*)- K+. - Aubert B; Barate R; Bona M; Boutigny D; Couderc F; Karyotakis Y; Lees JP; Poireau V; Tisserand V; Zghiche A; Grauges E; Palano A; et al. (Physical review letters, 2007)