1 . SOCIAL SECURITY FOR MIGRANT WORKERS - COMMUNITY RULES - RESTRICTION OF ADVANTAGES RESULTING FROM THE APPLICATION OF COMMUNITY REGULATIONS - MAINTENANCE OF ADVANTAGES OBTAINED UNDER NATIONAL LEGISLATION ALONE ( EEC TREATY , ARTS 48 TO 51 ) 2 . SOCIAL SECURITY FOR MIGRANT WORKERS - BENEFITS - NATIONAL RULES AGAINST OVERLAPPING - UNEMPLOYMENT BENEFIT - BENEFIT SUBJECT UNDER NATIONAL LEGISLATION TO FITNESS FOR WORK - FITNESS FOR WORK RECOGNIZED - REFUSAL TO GRANT ALLOWANCE BECAUSE OF AN INVALIDITY PENSION GRANTED BY ANOTHER MEMBER STATE - NOT PERMISSIBLE ( EEC TREATY , ART . 51 ; REGULATIONS NOS 1408/71 , ART . 12 ( 2 ), AND 574/72 OF THE COUNCIL )