1. ANP, Agência Nacional de Petróleo, Gás Natural e Bicombustíveis, Resolução n◦. 42, de 24 de novembro de 2004, Regulamento Técnico, n◦. 04/2004, Diário Oficial da União, Brasília.
2. ASTMD6751, Test method for determination of free and total glycerine in B 100 biodiesel methyl esters by gas chromatography, ASTM International, 2007, Available in: www.astm.org.
3. European Committee for Standardization, norms EN14214 and EN14106, 2003.
4. Simultaneous determination of glycerol, and mono-, di- and triglycerides in vegetable oil methyl esters by capillary gas chromatography;Plank;J. Chromatogr. A,1995
5. Determination of free glycerol in biodiesel;Hájek;Eur. J. Lipid Sci. Technol.,2006