Fractional Variations for Dynamical Systems: Hamilton and Lagrange   Approaches
  Fractional generalization of an exterior derivative for calculus of variations is defined. The Hamilton and Lagrange approaches are considered. Fractional Hamilton and Euler-Lagrange equations are derived. Fractional equations of motion are obtained by fractional variation of Lagrangian and Hamiltonian that have only integer derivatives. 
Vasily E. Tarasov