@article{02163652, title = {Symplectic difference systems: oscillation theory and hyperbolic Pr\"ufer transformation.}, journal = {Abstract and Applied Analysis}, volume = {2004}, year = {2004}, pages = {285-294}, doi = {10.1155/S108533750430607X}, zbl = {1074.39005}, language = {en}, url = {http://dml.mathdoc.fr/item/02163652} }
Došlý, Ondřej. Symplectic difference systems: oscillation theory and hyperbolic Prüfer transformation.. Abstract and Applied Analysis, Tome 2004 (2004) pp. 285-294. doi : 10.1155/S108533750430607X. http://gdmltest.u-ga.fr/item/02163652/