1. S. A. Amitsur, Radicals of polynomial rings,Canad. J. Math.,8 (1956), 355–361.
2. N. Divinsky,Rings and radicals, Allen and Unwin (1965).
3. N. Divinsky, Unequivocal rings,Canad. J. Math.,27 (1975), 679–690.
4. B. J. Gardner, Some remarks on radicals of rings with chain conditions.U. of Tasmania Technical Report,4 (1972).
5. N. Jacobson,Structure of rings, AMS Coll. Publ. (1964).