++++ 1 . PROCEDURE - PRELIMINARY RULING - JURISDICTION OF THE COURT - LIMITS ( EEC TREATY, ARTICLE 177 ) 2 . FREE MOVEMENT OF PERSONS - MIGRANT WORKERS - INSURANCE - ' LEGISLATION ' WITHIN THE MEANING OF REGULATION N . 3 OF THE COUNCIL OF THE EEC - CONCEPT 3 . FREE MOVEMENT OF PERSONS - MIGRANT WORKERS - INSURANCE - ARTICLES 27 AND 28 OF REGULATION N . 3 OF THE COUNCIL OF THE EEC - CONDITIONS OF APPLICATION 4 . FREE MOVEMENT OF PERSONS - MIGRANT WORKERS - INSURANCE - WIDOW'S PENSION GRANTED UNDER THE NETHERLANDS LEGISLATION IN FAVOUR OF WIDOWS AND ORPHANS - ASSIMILATION OF COMPLETED INSURANCE PERIODS UNDER THE NETHERLANDS LEGISLATION ON INVALIDITY ( REGULATION N . 3 OF THE COUNCIL OF THE EEC, ARTICLES 27 AND 28; REGULATION N . 130 OF THE COUNCIL OF THE EEC, ARTICLE 7 ( B ) ) 5 . FREE MOVEMENT OF PERSONS - MIGRANT WORKERS - INSURANCE - ' BENEFITS ALREADY PAID ' WITHIN THE MEANING OF ARTICLE 28 OF REGULATION N . 3 OF THE COUNCIL OF THE EEC - CONCEPT