“Multiple isozymes of heparan sulfate/heparin GlcNAc N-deacetylase/GlcN N-sulfotransferase. Structure and activity of the fourth member, NDST4”. The Journal of
Molecular cloning and characterization of an N-acetylglucosamine-6-O-sulfotransferase. J Biol Chem. 1998 Aug 28; 273(35): 22577-83. doi: 10.1074/jbc.273