Patricia Hall is Associate Professor of Music Theory at the Department of Music, University of California, Santa Barbara. She is the author of A View of Berg's 'Lulu' through the Autograph Sources (1997). She has also contributed to several works including The Cambridge Companion to Alban Berg (1996) and has written articles and reviews for a number of journals. Friedemann Sallis is Professor titulaire at the Departement de musique, Universite de Moncton. He is the author of An Introduction to the Early Works of Gyorgy Ligeti (1996). He also contributed to Music of the Twentieth-Century Avant-Garde (L. Sitsky ed., 2002) and has published numerous articles on music of the nineteenth and twentieth centuries.