@article{05836308, title = {Hyperbolic systems equivalent to the wave equation.}, journal = {Sibirskij Matematicheskij Zhurnal}, volume = {50}, year = {2009}, pages = {19-27}, zbl = {1224.35245}, language = {en}, url = {http://dml.mathdoc.fr/item/05836308} }
Gordienko, V.M. Hyperbolic systems equivalent to the wave equation.. Sibirskij Matematicheskij Zhurnal, Tome 50 (2009) pp. 19-27. http://gdmltest.u-ga.fr/item/05836308/