The ring of upper triangular invariants as a module over the Dickson invariants. H.E.A. Campbell; I.P. Hughes — 1996 Mathematische Annalen
On the ring of invariants of F*2n. H.E.A. Campbell; I. Hughes — 1991 Commentarii mathematici Helvetici
Polynomial algebras over the Steenrod algebra. H.E.A. Campbell; P.S. Selick — 1990 Commentarii mathematici Helvetici