@article{MAN_1970__184_161906,
     author = {G. PANTELIDIS},
     title = {Approximationstheorie f\"ur metrische lineare {R\"aume.}},
     journal = {Mathematische Annalen},
     pages = {30--48},
     publisher = {mathdoc},
     volume = {184},
     year = {1970},
     zbl = {0175.42001},
     url = {http://geodesic.mathdoc.fr/item/MAN_1970__184_161906/}
}