2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/11295We present a differential studies of 550 Cepheids observed in the LMC and the SMC by the EROS microlensing survey.5 pages, Latex file with 3 .ps figures. IAU 189, fundamental stellar properties : the interaction between observation and theory, Sydney, January 1997Astrophysicstext