British Standards Institution,Leather – Chemical tests – Determination of certain azo colourants in dyed leathers,DD CEN  ISO /TS 17234:2003 published on 3 September 2003,
British Standards Institution,Textiles – Methods for determination of certain aromatic amines derived from azo colourants – Part 1: Detection of the use of certain azo colourants accessible without extraction,BS EN 14362-1:2003 published on 25 November 2003,
British Standards Institution,Textiles – Methods for determination of certain aromatic amines derived from azo colourants – Part 2: Detection of the use of certain azo colourants accessible by extracting the fibres,BS EN 14362-2:2003 published on 25 November 2003,