2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44855A sufficient condition for the confinement of quarks is presented. Quarks are shown to be unobservable. Colour singlets are however, observables. The results of deep inelastic scattering are discussed. We argue that QCD does not exhibit a deconfining transition.5 pages, MZ-TH/93-03, DIAS-STP-93-04High Energy Physics - Phenomenologytext