Families of k-derivations on k-algebras

Abstract: Let A be an integral k-algebra of finite type over a field k of characteristic zero. Let be a family of k-derivations on A and the A-module spanned by . In this paper, we generalise a result due to Nowicki and construct an element of such that . Such a derivation is called -minimal. Then we establish a density theorem for -minimal derivations in . [Copyright &y& Elsevier]