title: Comment on "low temperature acoustic properties of amorphous silica and the tunneling model".
authors: Kirchhoff-Institut für Physik, Universität Heidelberg Albert-Ueberle-Strasse 3-5, 69120 Heidelberg, Germany.
authors: J
authors: J
authors: Classen
authors: C
authors: C
authors: Enss
authors: S
authors: S
authors: Hunklinger