@article{MZ_1964__86_170345,
     author = {Helmut Werner},
     title = {On the rational {Tschebyscheff} operator.},
     journal = {Mathematische Zeitschrift},
     pages = {317--326},
     publisher = {mathdoc},
     volume = {86},
     year = {1964},
     zbl = {0206.07504},
     url = {http://geodesic.mathdoc.fr/item/MZ_1964__86_170345/}
}