Fundamentals of Celestial Mechanics
(J.M.A. Danby). About $30. Second edition last printed in 1992.
Other Good Orbital Dynamics Texts:
Solar System Dynamics
(C.D. Murray and
S.F. Dermott). About $80. Published in 1999.
Excellent introdution to
planetary dynamics written in a modern style at a graduate student level.
Orbital Motion (A.E. Roy). Fourth edition published in 2005.
Good General Solar System Information:
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