T. Pellegrini et al.,  "A corpus-based study of elderly and young speakers of European Portuguese: Acoustic correlates and their impact on speech recognition performance ", in Proc. of the 14th Annu. Conf. of the Int. Speech Communication Association (INTERSPEECH 2013), Bimbot, F., Cerisara, C., Fougeron, C., Gravier, G., Lamel, L., Pellegrino, F., and Perrier, P., Ed., Lyon, International Speech Communication Association, 2013, vol. 2, pp. 852-856