2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41242We present the results of a study of the semileptonic decays of the $B_c$-meson and the lowest lying doubly heavy baryons using the relativistic quark model. We do not employ a heavy quark mass expansion but keep the masses of the heavy quarks and hadronss finite. We calculate all relevant form factors and decay rates.Talk given at the XVIth International Workshop on High Energy Physics and Quantum Field Theory, 6-12 September 2001, MoscowHigh Energy Physics - Phenomenologytext