  Closed strings spinning in AdS_3 x S^3 x T^4 with mixed R-R and NS-NS
three-form fluxes are described by a deformation of the one-dimensional
Neumann-Rosochatius integrable system. In this article we find general
solutions to this system that can be expressed in terms of elliptic functions.
We consider closed strings rotating either in S^3 with two different angular
momenta or in AdS_3 with one spin. In order to find the solutions we will need
to extend the Uhlenbeck integrals of motion of the Neumann-Rosochatius system
to include the contribution from the flux. In the limit of pure NS-NS flux,
where the problem can be described by a supersymmetric WZW model, we find exact
expressions for the classical energy in terms of the spin and the angular
momenta of the spinning string.
