Nagaraj Mahajan Nima Mesgarani Hynek Hermansky Principal components of auditory spectro-temporal receptive fields. 1983-1987 2014 INTERSPEECH https://doi.org/10.21437/Interspeech.2014-452 conf/interspeech/2014 db/conf/interspeech/interspeech2014.html#MahajanMH14