Ferrario, Lilia2025-06-242025-06-241405-2059ORCID:/0000-0002-0485-0518/work/162369275http://www.scopus.com/inward/record.url?scp=11844306865&partnerID=8YFLogxKhttps://hdl.handle.net/1885/733764654I argue that the observational evidence for white dwarf-white dwarf mergers supports the view that they give rise to ultra-massive white dwarfs or neutron stars through accretion induced collapse. The implications for the progenitors of Type Ia SNe are discussed.2enStars: NeutronStars: SupernovaeWhite dwarfs200410.1017/s025292110015211x11844306865