@article{oai:kanazawa-u.repo.nii.ac.jp:00010516,
 author = {Kobayashi, Kenta},
 issue = {8},
 journal = {Proceedings of the Japan Academy Series A: Mathematical Sciences},
 month = {Jan},
 note = {In a recent paper in this Proceedings, H. Okamoto presented a parameterized family of continuous functions which contains Bourbaki's and Perkins's nowhere differentiable functions as well as the Cantor-Lebesgue singular function. He showed that the function changes it's differentiability from 'differentiable almost everywhere' to 'non-differentiable almost everywhere' at a certain parameter value. However, differentiability of the function at the critical parameter value remained unknown. For this problem, we prove that the function is non-differentiable almost everywhere at the critical case. © 2009 The Japan Academy.},
 pages = {101--104},
 title = {On the critical case of Okamoto's continuous non-differentiable functions},
 volume = {85},
 year = {2009}
}