The correspondence includes letters from: Emily Anderson, Willi Apel, Jacques Barzun, Hans Bodmer, James D. Bolle, Patrick Boylan, Martin Breslauer, Manfred Bukofzer, Adam Carse, Charles Cudworth, Thurston Dart, Winton Dean, Helmuth Domizlaff, Heinrich Eisemann, Fritz Ernst, Austin Faricy, Everett Helm, Paul Hindemith, Anthony von Hoboken, Paul Hooreman, Alexander Hyatt King, Leonardo Lapiccirella, François Lesure, Folke Lindberg, Carlos Enrique Vargas Méndez, Kurt Merlander, Lawrence K. Moss, Oliver Neighbour, Cecil Bernard Oldman, Alice Posnansky, Jean-Pierre Rampal, Joan Rimmer, Percy A. Scholes, Adolf Seebass, Nicolas Slonimsky, Ernst Weil, Jacob Weinberg and many antiquarian houses.