@article{10_4064_fm_65_3_351_358,
     author = {Jack Ceder},
     title = {Differentiable roads for real functions},
     journal = {Fundamenta Mathematicae},
     pages = {351--358},
     publisher = {mathdoc},
     volume = {65},
     number = {3},
     year = {1969},
     doi = {10.4064/fm-65-3-351-358},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-65-3-351-358/}
}