1. Department of Audiology, University of Ferrara, Ferrara, Italy
2. Department of Clinical Sciences, University of Umea, Umea, Sweden
3. Department of Audiology, Southern Illinois University School of Medicine, Springfield, IL, U.S.A.
4. Department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, MA, U.S.A.
5. Institute of Physiology and Pathology of Hearing, Warsaw, Poland