++++ 1 . MEASURES ADOPTED BY COMMUNITY INSTITUTIONS - DECISION OF THE HIGH AUTHORITY TAKEN WITH THE UNANIMOUS ASSENT OF THE COUNCIL - AMENDMENT - POWERS OF THE HIGH AUTHORITY 2 . MEASURES ADOPTED BY COMMUNITY INSTITUTIONS - VALIDITY - CONDITIONS OF ESSENTIAL PROCEDURAL REQUIREMENTS - PROVISIONS RELATING THERETO - PROHIBITION ON THE EXTENSION OF THEIR APPLICATION 3 . COMMON FINANCIAL ARRANGEMENTS - EQUALIZATION OF FERROUS SCRAP - UNIT OF ACCOUNT - FUNCTION ( ECSC TREATY, ARTICLE 53 ) 4 . COMMON FINANCIAL ARRANGEMENTS - EQUALIZATION OF FERROUS SCRAP - CONTRIBUTIONS - CALCULATION IN UNITS OF ACCOUNT - RATE OF EXCHANGE APPLICABLE DURING ACCOUNTING PERIODS ( ECSC TREATY, ARTICLE 53 ) 5 . COMMON FINANCIAL ARRANGEMENTS - EQUALIZATION OF FERROUS SCRAP - DISCRIMINATORY RULES - AMENDMENT - ABSENCE OF VESTED RIGHTS