@article{MZ_1978__160_172669,
     author = {Walter Tholen and Reinhard B\"orger},
     title = {Cantors {Diagonalprinzip} f\"ur {Kategorien.}},
     journal = {Mathematische Zeitschrift},
     pages = {135--138},
     year = {1978},
     volume = {160},
     zbl = {0363.04002},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__160_172669/}
}