DIN EN ISO 8968-4-2016 牛奶和奶制品.氮含量的測定.第4部分:蛋白質和非蛋白質氮含量的測定和純蛋白質含量的計算 (參考方法)(ISO 8968-4-2016).德文版本EN ISO 8968-4-2016
Milk and milk products - Determination of nitrogen content - Part 4: Determination of protein and non-protein nitrogen content and true protein content calculation (Reference method) (ISO 8968-4:2016); German version EN ISO 8968-4:2016