2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/21643We point out that ferromagnetic superconductors with triplet pairing and strong spin-orbit coupling are even in the simplest case at least two-band superconductors. The Gor'kov type formalism for such superconductors is developed and the Ginzburg-Landau equations are derived. The dependence of the critical temperature on the concentration of ordinary point-like impurities is found. Its nonuniversality could serve as a qualitative measure of the two-band character of ferromagnetic superconductors. The problem of the upper critical field determination is also discussed.8 pages, no figure; important changes with respect to the previous versions due to the correction of a mistake: in this new version, a more general form is considered for the order parameter (the two-components of the order parameter were considered before as equal, which is in general not true) ; submitted to Physical Review BSuperconductivitytext