2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/64628We give a geometric characterization of extremal sets in ell_p spaces that generalizes our previous result for such sets in Hilbert spaces.13 pages, corrected some misprints and shortened Lemma 3.1Metric GeometryFunctional Analysis46B20, 46E30text