Strings in Meson and Baryon Physics
  The relativistic string with massive ends (the meson model) and four various string baryon models: q-qq, q-q-q, Y and $\Delta$ are considered. In particular, the rotational motions for all these systems are applied to describing the leading Regge trajectories, and also the classical dynamics beyond the usual rectilinear string rotations is studied. For the string meson model the two types of quasirotational motions (disturbances of the planar uniform rotations) are obtained. They are oscillatory motions in the form of stationary waves in the rotational plane and in the orthogonal direction. The analysis of the stability problem for the rotational motions for all mentioned string configurations shows that these motions for the Y and q-q-q models are unstable on the classical level. 
G. S. Sharov