@InProceedings{huth94a,
  author = 	{M. Huth and A. Jung and K. Keimel},
  title = 	{Linear Types, Approximation, and Topology},
  pages = 	{110--114},
  booktitle = 	{Logic in Computer Science},
  year = 	1994,
  publisher = 	{IEEE Computer Society Press},
  abstract = 	{We enrich the $*$-autonomous category of complete
		  lattices and maps preserving all suprema with the
		  important concept of {\em approximation\/} by
		  specifying a $*$-autonomous full subcategory LFS of
		  {\em linear FS-lattices\/}. This is the greatest
		  $*$-autonomous full subcategory of linked
		  bicontinuous lattices. The modalities ! and ?
		  mediate a duality between the upper and
		  lower powerdomains. The distributive objects in LFS
		  give rise to the {\em compact closed\/}
		  $*$-autonomous full subcategory CD of {\em
		  completely distributive lattices\/}. We characterize
		  algebraic objects in LFS by forbidden substructures
		  `\`a la Plotkin'.}
}