1. ISO 660–1983 (E). Animal and vegetable fats and oils––determination of acid value and acidity. International Organization for Standardization, Switzerland
2. Firestone D (ed) (1996) Official methods and recommended practices of the American Oil Chemists Society. Method Ca 5a–40. Free fatty acids, 4th edn. American Oil Chemists’ Society, Champaign
3. Firestone D (1996) In: Perkins EG, Erickson MD (eds) Regulation of frying fat and oil in deep frying. Chemistry, nutrition, and practical application. ACCS Press, Champaign, pp 323–334
4. Tur’yan Ya. I., O. Yu. Berezin, Kuselman I, Shenhar A (1996) pH-metric determination of acid values in vegetable oils without titration. J Am Oil Chem Soc 73:295–301
5. CRC Handbook of Chemistry and Physics (1986–1987) In: Weast RC (ed) 67th edn. CRC Press, Inc., Boca Raton, p. D218