23833 J. Billingham/A. King: Wave motion. Cambridge UP 2006, 460p. Eur 56.

19237 Damiano Foschi: On the regularity of multilinear forms associated
to the wave equation. PhD thesis Princeton UP 2000, 108p.

5534 Paul Günther: Huygens' principle and Hadamard's conjecture.
Math. Intell. 13/2 (1991), 56-62. On a problem connected with hyperbolic
differential equations posed in 1923 by Jacques Hadamard.

23729 Michael Junk: Hyperbolic conservation laws and industrial applications.
In 23599 Meister/Struckmeier 2002, 1-56.

23599 Andreas Meister/Jens Struckmeier: Hyperbolic partial differential equations.
Vieweg 2002, 320p. Eur 44.