Judgment of the Court (Second Chamber) of 20 January 2005 in Case C-225/02 (reference for a preliminary ruling by the Juzgado de lo Social n° 3 de Orense): Rosa García Blanco v Instituto Nacional de la Seguridad Social (INSS), Tesorería General de la Seguridad Social (TGSS) (Social security of migrant workers — Old age — Unemployment — Minimum periods of insurance — Periods of insurance taken into account for calculating the amount of benefits but not for acquiring the right to those benefits — Periods of unemployment — Aggregation)