@article{MM2_1987__58_155221,
     author = {N. Hadjisavvas and B. Nassopoulos},
     title = {\"Uber die {Existenz} gemeinsamer {Elemente} bester {Approximation} bez\"uglich zweier {Normen.}},
     journal = {Manuscripta mathematica},
     pages = {245--252},
     publisher = {mathdoc},
     volume = {58},
     year = {1987},
     zbl = {0643.41017},
     url = {http://geodesic.mathdoc.fr/item/MM2_1987__58_155221/}
}