1 . SOCIAL SECURITY FOR MIGRANT WORKERS - SOCIAL SECURITY BENEFITS - OVERLAPPING - LIMITATION - ENTITLEMENT BY VIRTUE OF A NATIONAL LEGISLATION ALONE - REDUCTION - PROHIBITION ( EEC TREATY , ARTICLE 51 ; REGULATION NO 1408/71 OF THE COUNCIL , ARTICLE 46 ( 3 )) 2 . SOCIAL SECURITY FOR MIGRANT WORKERS - INSURANCE PERIODS - DUPLICATION - SOCIAL SECURITY BENEFITS - RULES AGAINST OVERLAPPING - APPLICATION - CONDITION ( REGULATION NO 1408/71 OF THE COUNCIL , ARTICLE 46 ( 3 ))