00409nam a2200145Ia 4500003000900000008004100009040001600050080001500066100001400081245005400095260003900149300001000188650004100198650002400239IN-BaIIA211028s9999    xx            000 0 eng d  cIIA Library  a521.1bRYA  aRyabov, Y 3aAn elementary of celestial mechanicscRyabov, Y    aNew YorkbDover Publicationsc1959  a164p.  aAstronomy and astrophysics thesaurus  aCelestial mechanics