, TO THE ' ' SINGLE RATE ' ' . THE BELGIAN INSTITUTION CONSIDERED THAT , BY VIRTUE OF ARTICLE 51 ( 2 ) OF REGULATION NO 1408/71 , THAT ALTERATION MADE IT NECESSARY TO RECALCULATE THE BENEFITS IN ACCORDANCE WITH ARTICLE 46 OF THAT REGULATION . ON 2 NOVEMBER 1978 IT WAS INFORMED OF THE AMOUNT OF THE ITALIAN BENEFITS PAID ON 1 JANUARY 1976 AND , APPLYING BELGIAN PROVISIONS AGAINST THE OVERLAPPING OF BENEFITS AND TAKING ACCOUNT OF THE VALUE OF THAT AMOUNT AS AT 1 JANUARY 1976 , CLAIMED FROM MR SINATRA FOR THE PERIOD FROM 1 JANUARY 1976 TO 31 JANUARY 1979 AN OVERPAYMENT OF BFR 38 800 .
3 THE COUR DU TRAVAIL , MONS , CONSIDERING THAT THE OUTCOME OF THE MAIN ACTION DEPENDED UPON THE INTERPRETATION OF ARTICLE 51 OF REGULATION NO 1408/71 OF THE COUNCIL , REFERRED TO THE COURT THE FOLLOWING QUESTIONS FOR A PRELIMINARY RULING :
' ' 1 . DOES THE ' REVALORIZATION ' REFERRED TO IN THE HEADING TO ARTICLE 51 OF REGULATION NO 1408/71 OF 14 JUNE 1971 CONSTITUTE THE GENERAL FRAMEWORK OF APPLICATION OF PARAGRAPHS ( 1 ) AND ( 2 ) OF THAT ARTICLE WITH THE RESULT THAT THE CASES MENTIONED IN PARAGRAPH ( 2 ) ONLY COVER INSTANCES IN WHICH THERE IS A REVALORIZATION OR INCREASE IN BENEFITS EVEN THOUGH THE WORD ' ALTER ' USED IN ARTICLE 51 ( 2 ) USUALLY MEANS BOTH IMPROVEMENT AND DETERIORATION?
2.IS THE ' METHOD OF DETERMINING OR THE RULES FOR CALCULATING BENEFITS ' ' ALTERED ' WITHIN THE MEANING OF ARTICLE 51 ( 2 ) OF REGULATION NO 1408/71 WHERE THERE IS AN ALTERATION ONLY IN THE POSITION OF THE PERSON INSURED UNDER A SOCIAL SECURITY SCHEME WHICH REQUIRES , IN HIS CASE , APPLICATION BY THE BELGIAN INSTITUTION OF A DIFFERENT RULE OF BELGIAN LAW RELATING TO THE AMOUNT OF THE BELGIAN UNDERGROUND MINEWORKERS ' INVALIDITY PENSION AWARDED TO HIM WITH THE EFFECT OF REDUCING THE PENSION ( ARTICLE 4 ( 1 ) ( 4 ) OF THE ROYAL DECREE OF 19 NOVEMBER 1970 ), WITHOUT ANY CHANGE HAVING OCCURRED AT THAT TIME IN THE BELGIAN LEGISLATIVE PROVISIONS AS SUCH RELATING TO THE MANNER OF FIXING BENEFITS OR IN THOSE CONCERNING THE RULES FOR CALCULATING BENEFITS?
3.MUST ARTICLE 51 ( 2 ) OF REGULATION ( EEC ) NO 1408/71 BE INTERPRETED AS MEANING THAT AN ALTERATION ONLY IN THE AMOUNT OF THE INVALIDITY PENSION AWARDED BY THE COMPETENT BELGIAN INSTITUTION TO A PERSON INSURED UNDER THE SOCIAL SECURITY SCHEME WHICH HAS THE EFFECT OF REDUCING THAT AMOUNT , IN APPLICATION OF ARTICLE 4 ( 1 ) ( 4 ) OF THE ROYAL DECREE OF 19 NOVEMBER 1970 , ENTAILS A RECALCULATION OF THE BENEFITS IN ACCORDANCE WITH ARTICLE 46 OF REGULATION NO 1408/71?
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4 IT IS CLEAR FROM AN ANALYSIS OF THOSE QUESTIONS THAT THE NATIONAL COURT IS ESSENTIALLY SEEKING TO ASCERTAIN WHETHER , ACCORDING TO ARTICLE 51 OF REGULATION NO 1408/71 ,