2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/153351We apply Mackey procedure of classifying projective systems of imprimitivity to a thorough study of the projective unitary irreducible representations of the Galilei group in 1+3 and 1+2 dimensions.20 pages, LATEXQuantum AlgebraProjective Systems of Imprimitivitytext