@article{MZ_1970__115_171359,
     author = {Claus Michael Ringel},
     title = {Eine {Charakterisierung} der {Homotopiekategorie} der {CW-Komplexe.}},
     journal = {Mathematische Zeitschrift},
     pages = {359--365},
     publisher = {mathdoc},
     volume = {115},
     year = {1970},
     zbl = {0188.28401},
     url = {http://geodesic.mathdoc.fr/item/MZ_1970__115_171359/}
}