  The structure of a single flux line in (s+d)-wave superconductors has been
analyzed within the Ginzburg-Landau (GL) model generalized for two order
parameter components. The fourfold symmetric singular vortex solution is shown
to be unstable in a certain range of the GL parameters with respect to the
mutual shift of s- and d- wave unit vortices. The resulting nonsingular vortex
structure is studied both analytically and numerically.
