1. Evers, J. M. (1999). Determination of fat in butter — a review. IDF Bulletin No. 340, Brussels: International Dairy Federation.
2. An accurate and rapid method for the direct determination of fat in butter, butter-margarine blends and milkfat spreads;Evers;International Dairy Journal,1999
3. A precise method to measure the total fat content of spreadable fats;Evers;International Dairy Journal,2001
4. IDF (1991). International Standard 135B. Milk and milk products. Precision characteristics of analytical methods — outline of collaborative study procedure. Brussels: International Dairy Federation.
5. ISO (1994). International Standard 5725. Accuracy (trueness and precision) of measurement methods and results — part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method. Geneva: International Standards Organisation.