@article{10_4064_fm_48_3_251_263,
     author = {J. de Groot and R. McDowell},
     title = {Extension of mappings on metric spaces},
     journal = {Fundamenta Mathematicae},
     pages = {251--263},
     publisher = {mathdoc},
     volume = {48},
     number = {3},
     year = {1959},
     doi = {10.4064/fm-48-3-251-263},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-48-3-251-263/}
}