Álvaro Aballe Villero, M. Bethencourt Núñez, F. J. Botana Pedemonte, M. Marcos Bárcena, and J. M. Sánchez-Amaya, “Alternatives to chrome in the aluminium surface finishing industry Low environmental impact surface treatments”, Rev. metal., vol. 37, no. 1, pp. 49–62, Feb. 2001.