Sur une g\'en\'eralisation de l'op\'erateur fractionnaire
  The goal of this communication is to propose a generalized notion of the "traditional derivative". This generalization includes the fractional derivatives such as the Riemann-Liouville, Gruenwald-Letnikov, Weyl, Riesz, Caputo, Marchaud derivatives and other variants as special cases. The approach is useful to describe mechanical problems in material systems with microstructures without characteristic scale such as self-similar and fractal materials. 
Thomas Michelitsch (IJLRA), G\'erard Maugin (IJLRA), Shahram Derogar,   Andrzeij Nowakowski (University of Sheffield), Nicol...
physics.class-ph