1 . SOCIAL SECURITY FOR MIGRANT WORKERS - INVALIDITY INSURANCE - BENEFIT GRANTED ON THE BASIS OF NATIONAL LEGISLATION ALONE - ALTERATION IN CASE OF FULFILMENT OF THE CONDITIONS FOR THE GRANT OF BENEFITS OBTAINED THROUGH THE LEGISLATION OF ANOTHER MEMBER STATE ( ARTICLE 28 ( 1 ) ( F ) AND ( G ) OF REGULATION NO 3 OF THE COUNCIL ; ARTICLE 49 OF REGULATION NO 1408/71 OF THE COUNCIL ) 2 . SOCIAL SECURITY FOR MIGRANT WORKERS - INVALIDITY INSURANCE - BENEFITS - CLAIM - LODGING - PROCEDURE ( ARTICLE 30 OF REGULATION NO 4 OF THE COUNCIL ; ARTICLE 36 ( 1 ) OF REGULATION NO 574/72 OF THE COUNCIL )