@article{10_4064_cm_31_1_129_136,
     author = {Michael J. Evans},
     title = {On continuous functions and the approximate symmetric derivatives},
     journal = {Colloquium Mathematicum},
     pages = {129--136},
     publisher = {mathdoc},
     volume = {31},
     number = {1},
     year = {1974},
     doi = {10.4064/cm-31-1-129-136},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-31-1-129-136/}
}