sql - あいまいな外部結合が含まれているため、SQL ステートメントを実行できませんでした。どこ？

Question

これを実行するとエラー メッセージが表示されます。なぜなのかご存知ですか？Access のデザイン ビューを使用して作成しました。

SELECT  [Sales structure].Cluster ,
        [Sales structure].Country ,
        [Transaction details].[Sales company code] ,
        [Sales structure].[Sales company name] ,
        YEAR([Transaction details].[YYYY-MM-DD]) AS [Year] ,
        MONTH([Transaction details].[YYYY-MM-DD]) AS [Month] ,
        SUM([Transaction details].[Sales volume LOC]) AS Total ,
        [Transaction details].[Currency code] ,
        Currencies.[CUR/EUR] AS [Currency rate]
FROM    Items ,
        Currencies
        RIGHT JOIN ( [Sales structure]
                     RIGHT JOIN [Transaction details] ON [Sales structure].[Sales company code] = [Transaction details].[Sales company code]
                   ) ON Currencies.[Currency code] = [Transaction details].[Currency code]
GROUP BY [Sales structure].Cluster ,
        [Sales structure].Country ,
        [Transaction details].[Sales company code] ,
        [Sales structure].[Sales company name] ,
        YEAR([Transaction details].[YYYY-MM-DD]) ,
        MONTH([Transaction details].[YYYY-MM-DD]) ,
        [Transaction details].[Currency code] ,
        Currencies.[CUR/EUR]
HAVING  ( ([Transaction details].[Currency code] = [Currencies].[Currency code]) )
ORDER BY YEAR([Transaction details].[YYYY-MM-DD]) ,
        MONTH([Transaction details].[YYYY-MM-DD]) ;