1 . COMMUNITY LAW - PRINCIPLES - PROHIBITION OF DISCRIMINATION BASED ON NATIONALITY - TERRITORIAL SCOPE - LOCATION OF LEGAL RELATIONSHIPS WITHIN THE TERRITORY OF THE COMMUNITY - CRITERIA 2 . FREE MOVEMENT OF PERSONS - WORKERS - EQUALITY OF TREATMENT - NATIONAL OF A MEMBER STATE EMPLOYED BY AN UNDERTAKING OF ANOTHER MEMBER STATE - TEMPORARY WORK OUTSIDE THE COMMUNITY - RETENTION OF AFFILIATION TO THE SOCIAL SECURITY SCHEME OF THE MEMBER STATE IN WHICH THE UNDERTAKING IS ESTABLISHED ( EEC TREATY , ART . 48 ; REGULATION NO 1612/68 OF THE COUNCIL )