Annihilators of nilpotent elements. Klein, Abraham A. (2005) International Journal of Mathematics and Mathematical Sciences
Another counterexample to a conjecture of Zassenhaus. Hertweck, M. (2002) Beiträge zur Algebra und Geometrie
Associative and Lie algebras of quotients. F. Perera, M. Siles Molina (2008) Publicacions Matemàtiques