Application of the Kovacic algorithm for the investigation of motion of a heavy rigid body with a fixed point in the Hess case

In 1890 German mathematician and physicist W. Hess found new special case of integrability Euler - Poisson equations motion a heavy rigid body with fixed point. 1892 P. A. Nekrasov proved that the solution problem point under conditions reduces to integrating second order linear differential equation. this paper corresponding equation is derived its coefficients are presented in rational form. Using Kovacic algorithm, we liouvillian solutions exists only case, when moving Lagrange top, or constant area integral zero.