CPC Subgroup
C01B 21/0975 Full Title
Nitrogen; Compounds thereof > Compounds containing nitrogen and non-metals (C01B21/06, C01B21/08 take precedence) > containing phosphorus atoms
C01B 21/0975 Nitrogen; Compounds thereof > Compounds containing nitrogen and non-metals (C01B21/06, C01B21/08 take precedence) > containing phosphorus atoms