10 key problems in stellar dynamics: in retrospect
  This list of 10 problems and their subsequent discussion by prominent scholars at the workshop in Geneva Observatory, 1993, were published in Lecture Notes in Physics, 1994, not too reachable now. The problems cover Theory, Computer Simulations (including regarding Lyapunov exponents and the search of codes radically differing from standard N-body ones) and Observations. The elapsed 20 year period enables to reveal the occurred developments, if any, on each problem and the validity of predictions made by experts. 
V. G. Gurzadyan
astro-ph.GA physics.comp-ph