2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47512We develop the perturbative QCD formalism for inclusive heavy hadron decays. Transverse degrees of freedom of partons are introduced to facilitate the factorization of the heavy hadron decays.9 pages, Latex; Invited talk given at pppp workshop(Oct.30-Nov.2,1997), APCTP, Seoul, KoreaHigh Energy Physics - Phenomenologytext