1. Department of Speech and Hearing Science, University of Illinois Urbana-Champaign, Champaign, Illinois 61820, USA
2. Voice Biomechanics and Acoustics Laboratory, Department of Communicative Sciences and Disorders, Michigan State University, East Lansing, Michigan 48824, USA
3. Department of Energy, Politecnico di Torino, Torino, Italy
4. Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy