1. On the kernel of some derivations of K(x1,…,xn);Ayad;Comm. Algebra,2002
2. A note on subrings of constants of an affine domain;Baba;Math. J. Toyama Univ.,1993
3. J. Berson, Derivations on polynomial rings over a domain, Master’s Thesis, University of Nijmegen, 1999.
4. D. Daigle, Locally nilpotent derivations, in: Lecture Notes for the 26th Autumn School of Algebraic Geometry, Łukȩcin, Poland, September 2003.
5. Computing invariants of algebraic groups in arbitrary characteristic;Derksen;Adv. Math.,2008