2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/57396The ``Kaluza-Klein-type'' geometric structure appropriate to study the central extension of the Galilei group and non-relativistic physics is reviewed.Talk given at the {\rm XIX}th {\it Int. Coll. on Group Theor. Meths. in Physics, Salamanca'92}. Del Olmo, Santander, Guilarte (eds) p. 446. Anales de Fisica Monografias (1993). Plain TeX, 4 pages, no figuresMathematical Physicstext