@STRING{tplp    = "Theory and Practice of Logic Programming"}
@Article{gekasc11b,
  author =       "M. Gebser and R. Kaminski and T. Schaub",
  title =        "Complex Optimization in Answer Set Programming",
  journal =      tplp,
  volume =       11,
  number =       "4-5",
  pages =        "821-839",
  year =         2011
}