1. Nil derivations;Chung;J. Algebra,1985
2. Remark on nilpotency of derivations;Chung,1984
3. Nilpotency of derivatives on an ideal;Chung,1984
4. Nilpotency of derivations, II;Chung,1984
5. L. O. Chung, A. Kovacs, and J. Luh, Algebraic derivations of prime rings, preprint.