On isotype subgroups of abelian groups John M. Irwin; Elbert A. Walker — 1961 Bulletin de la Société Mathématique de France
On N-high subgroups of abelian groups John M. Irwin; K. Benabdallah — 1968 Bulletin de la Société Mathématique de France
On elongations of totally projective p -groups by p ω + n -projective p -groups László Fuchs; John M. Irwin — 1982 Czechoslovak Mathematical Journal