DIN 52241-7:1986 制造玻璃原料的檢驗.對含碳酸鈣鎂不小于95%的白云石的化學分析.按氧化錳計算的錳含量測定
Analysis of raw materials used in glass production; chemical analysis of dolomite containing not less than 95 % of calcium magnesium carbonate; determination of manganese content calculated as MnO