1. V. A. Andrunakievič, Radicals in associative rings I,Mat. Sb. (N.S.),44 (1958), 179–212 (Russian),Amer. Math. Soc. Transl.,55 (1966), 95–128.
2. V. A. Andrunakievič, Radicals in associative rings II,Mat. Sb. (N.S.),55 (1961), 329–346 (Russian),Amer. Math. Soc. Transl.,55 (1966), 129–149.
3. V. A. Andrunakievič and J. M. Rjabuhin, Rings without nilpotent elements and completely simple ideals,Dokl. Akad. Nauk SSSR,180, (1968),Soviet Math. Dokl.,9 (1968), 565–568.
4. V. A. Andrunakievič and J. M. Rjabuhin, Fully idempotent rings and the generalized nil-radical,Dokl. Akad. Nauk SSSR,201 (1971),Soviet Math. Dokl.,12 (1971), 1742–1746.
5. N. J. Divinsky,D-regularity,Proc. Amer. Math. Soc.,9 (1958), 62–71.