On some properties of Lipschitz mappings of the real line into a normed space. Ponomarev, Stanislav; Turowska, Małgorzata — 2009 Sibirskij Matematicheskij Zhurnal
Lipschitz mappings, contingents, and differentiability. Ponomarev, S.P.; Turowska, Małgorzata — 2007 Sibirskij Matematicheskij Zhurnal