2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42814We have calculated the fermionic contributions to the flavour non-singlet structure functions in deep-inelastic scattering (DIS) at third order of massless perturbative QCD. We discuss their implications for the threshold resummation at the next-to-next-to-leading logarithmic accuracy.Presented at 11th International Workshop on Deep Inelastic Scattering (DIS 2003), St. Petersburg, 23-27 April, 2003, 5 pages, 2 figures; v2: one reference addedHigh Energy Physics - Phenomenologytext