2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/82611We present examples for the calculation of the distribution and fragmentation functions using the representation in terms of non-local matrix elements of quark field operators. As specific examples, we use a simple spectator model to estimate the leading twist quark distribution functions and the fragmentation functions for a quark into a nucleon or a pion.5 pages RevTeX, talk presented at the First ELFE School on Confinement Physics, 22-28 July 1995, Cambridge, EnglandNuclear TheoryHigh Energy Physics - Phenomenologytext