@Article{	  dixgotmar95,
  author	= {J\"{u}rgen Dix and Georg Gottlob and Viktor Marek},
  title		= {Reducing Disjunctive to Non-Disjunctive Semantics by
		  Shift-Operations},
  journal	= {Fundamenta Informaticae},
  year		= {1996},
  volume	= {XXVIII(1/2)},
  pages		= {87--100}
}