2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42933In this talk, I present a family unification in $Z_3$ orbifolded $E_8\times E_8^\prime$ heterotic strings. It is argued that trinification is a plausible candidate toward supersymmetric standard model at low energy.9 pages. Talk presented at String Phenomenology Workshop, Durham, England, July 29-Aug. 4, 2003High Energy Physics - Phenomenologytext