1. On the period and damping of polar motion;Groten;J. geophys. Res.,1991
2. 2 Lamb H. ,1932.Hydrodynamics6th edn, Cambridge University Press, Cambridge.
3. 3 Melchior P. ,1966.The Earth TidesPergamon Press, Oxford.
4. 4 Melchior P. ,1986.The Physics of the Earth’s CorePergamon Press, Oxford.
5. On ‘pathological oscillations’ of rotating fluids in the theory of nutation;Molodensky;J. Geodesy,1996