She is often praised for her technical virtuosity. Jim Santella of "The Buffalo News" writes "Like an iron fist in a velvet glove, the power of Celine Dion's voice is cloaked in a silky vibrato that betrays the intensity of her vocal commitment." Jeff Miers, also of "The Buffalo News", says of Dion "Her singing voice is absolutely extra-human. She hits notes in full voice, with a controlled vibrato and an incredible conception of pitch, like she's shucking an ear of corn." Stephen Holden of "The New York Times" states that Dion has "a good-sized arsenal of technical skills. She can deliver tricky melismas, produce expressive vocal catches and sustain long notes without the tiniest wavering of pitch. And as her duets ... have shown, she is a reliable harmony voice." In an interview with "Libération", Jean-Jacques Goldman notes that she has "no problem of accuracy or tempo". According to Kent Nagano, she is "a musician who has a good ear, a refinement, and a degree of perfection that is enviable". Charles Alexander of "Time" states, " voice glides effortlessly from deep whispers to dead-on high notes, a sweet siren that combines force with grace."