5Jack Boss, “Schoenberg' s Op. 22 Radio Talk and Developing Variation in Atonal Music”, Music Theory Spectrum, Vol. 14, No. 2 (Autumn, 1992), p. 130.
6Walter Frisch, Brahms and the Principle of Developing Variation, University of California Press, 1984, p. 24.
7Kofi Agawu , “Formal Perspectives on the Symphonies”, The Cambridge Companion to Brahms, edited by Michael Musgrave,Cambridge University Press , 1999.
8Jonalhan Dunsby, “Developing Variation”, in The Cambridge History of Western Music Theory, edited by Thomas Christensen , Cambridge University Press , 2002 , p. 911.
