Let D be a division ring finite dimensional over its center F. The goal of
this paper is to prove that for any positive integer n there exists a in D^(n);
the n-th multiplicative derived subgroup, such that F(a) is a maximal subfield
of D. We also show that a single depth-n iterated additive commutator would
generate a maximal subfield of D.Comment: We have made some editorial changes as well as changes in Lemma 9 and
  Theorem 1

Aaghabali, Mehdi