On The Brown-McCoy Radical Of Group Rings N. J. Groenewald — 1980 Publications de l'Institut Mathématique
A Note on Extensions of Bear and P.p.-rings N. J. Groenewald — 1983 Publications de l'Institut Mathématique
A Note On Units And Divisors Of Zero In Group Rings N. J. Groenewald; H. J. Schutte — 1982 Publications de l'Institut Mathématique