1. An encyclopedia of chemicals and drugs;The Merck Index,2001
2. United States Code of Federal Regulations, Title 27-Alcohol, Tobacco Products and Firearms, Chapter 1, Subpart C. Standards of Identity for distilled spirits; 2003.
3. Regulation (EC) No 110/2008 of the European Parliament and of the Council of 15 January 2008 on the definition, description, presentation, labelling and the protection of geographical indications of spirit drinks and repealing Council Regulation (EEC) No 1576/89. Official Journal of the European Union. L39/16-50. 13.2.2008.
4. The enzymes;Dixon,1964
5. Pectic enzymes in fruit and vegetable juice manufacture;Pilnik,1993