@article{CM_1967__18_1-2_170_0,
     author = {Felgner, Ulrich},
     title = {Untersuchungen \"uber das {Zornsche} {Lemma}},
     journal = {Compositio Mathematica},
     pages = {170--180},
     publisher = {P. Noordhoff N. V., Groningen},
     volume = {18},
     number = {1-2},
     year = {1967},
     mrnumber = {231722},
     zbl = {0168.25304},
     language = {de},
     url = {http://www.numdam.org/item/CM_1967__18_1-2_170_0/}
}