@InProceedings{Zho+Mul:Nonmon-1990,
  author =      {Yuli Zhou and Robert Muller},
  title =       {Domain Theory for Nonmonotonic Functions},
  booktitle =	{Proceedings of the Second
		International Conference on Algebraic and Logic Programming},
  pages =    	{144--157},
  volume =      {463},
  month =       {October},
  year =	{1990}, 
  publisher =	{Springer-Verlag, Lecture Notes in Computer Science},
  }