@article{MOMA_1970__74_177491,
     author = {Herbert Izbicki},
     title = {\"Uber {Unterb\"aume} eines {Baumes.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {56--62},
     publisher = {mathdoc},
     volume = {74},
     year = {1970},
     zbl = {0209.28102},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1970__74_177491/}
}