2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70249We study the arithmetic of certain del Pezzo surfaces of degree 2. We produce examples of Brauer-Manin obstruction to the Hasse principle, coming from 2- and 4-torsion elements in the Brauer group.24 pages, to appear in Proc. London Math. SocAlgebraic GeometryNumber Theory14G05; 12G05On the arithmetic of del Pezzo surfaces of degree 2text