@TechReport{TR069,
  author =	 "Maamar Saib and Yll Haxhimusa and Roland Glantz",
  institution =	 "PRIP, TU Wien",
  number =	 "PRIP-TR-069",
  title =	 "Building {I}rregular {G}raph {P}yramid {U}sing
                  {D}ual {G}raph {C}ontraction",
  year =	 "2002",
  url =		 "https://www.prip.tuwien.ac.at/pripfiles/trs/tr69.pdf",
  abstract =	 "In this technical report the new version of the
                  software Dgc tool is presented.This tool allows us
                  to build up irregular graph pyramids by dual graph
                  contraction.The graph pyramid consists of a stack of
                  levels (pair of graphs),each of which has a primal
                  level and its dual. Every successive level is a
                  reduced version of the level below. Primal level and
                  its dual represent a primal graph and its
                  dual,respectively. The primal graph base level of
                  the pyramid may represent a two dimensional image.",
}