@Misc{		  dix95lmps,
  author	= {J\"{u}rgen Dix},
  title		= {Characterizing Semantics of Logic Programs by Partial
		  Evaluation},
  howpublished	= {10 th International Congress of Logic, Methodology and
		  Philosophy of Science, Florence, Italy},
  month		= {August},
  year		= {1995},
  abstract	= { Our aim is to look from a more structural point of view
		  at the various semantics for logic programs with negation
		  that have been considered in the last years. Nearly all
		  semantics SEM are defined by associating with any program
		  $P$ a subset of its 3-valued Herbrand models
		  \[\mbox{SEM}(P)\subseteq
		  \mbox{MOD}^{Herbrand}_{3-val}(P).\] But a purely
		  model-theoretical investigation is not possible, because
		  all these semantics depend on the way the program is
		  written down. They are not invariant under classical
		  equivalence: \[P \Leftrightarrow P' \mbox{ \ does not imply
		  \ } \mbox{SEM}(P) = \mbox{SEM}(P').\] Therefore the
		  syntactic structure of the program $P$, partially
		  represented by its dependency graph ${\cal G}_P$, plays an
		  important role. We show that some particular {\em syntactic
		  transformations\/} suffice to determine certain semantics uniquely.}
}