@misc{El-Sabaa_F._M._Existence_1992,
 author={El-Sabaa, F. M.},
 volume={44},
 number={3},
 copyright={Creative Commons Attribution BY 4.0 license},
 address={Warszawa},
 journal={Archives of Mechanics},
 howpublished={online},
 year={1992},
 publisher={Polish Scientific Publishers IFTR},
 language={eng},
 type={Text},
 title={Existence of a periodic solution for Kovalevskaya top},
 URL={http://rcin.org.pl/Content/68357/PDF/WA727_18039_44-3-1992_AMS_El-Sabaa-08.pdf},
 keywords={Mechanika stosowana - czasopisma [KABA]},
}