@article{AMLG_1971__14_137851,
     author = {Kurt Sch\"utte and Hilbert Levitz},
     title = {A characterization of {Takeuti's} ordinal diagrams of finite order.},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {75--98},
     publisher = {mathdoc},
     volume = {14},
     year = {1971},
     zbl = {0244.02011},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1971__14_137851/}
}