@article{NUMA_1981__37_132728,
     author = {H. Ko{\ss}mann},
     title = {Differenzenverfahren zur {Berechnung} periodischer {L\"osungen} von hyperbolischen {Differentialgleichungen.}},
     journal = {Numerische Mathematik},
     pages = {219--234},
     publisher = {mathdoc},
     volume = {37},
     year = {1981},
     zbl = {0442.65098},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1981__37_132728/}
}