  Exchanged interactions in recently observed helical structure in LiCu2O2 is
probed by inelastic neutron scattering. The main conlusions of Refs. [1,2] are
confirmed: nn interactions in single chains are ferromagnetic and frustrated by
nnn antiferromagnetic ones. However, in apparent disagreement with Refs. [1,2]
double-chain interactions are found to be of the same order of magnitude as the
single-chain ones, and thus involved in the frustration mechanism.
  [1] Drechsler et al., cond-mat/0411418. [2] A. Gippius et al. Phys. Rev. B 70
(2004), R01426; cond-mat/0312576.
