Alvaro Francisco Huertas-Rosero Leif Azzopardi C. J. van Rijsbergen Eraser Lattices and Semantic Contents. 266-275 2009 QI http://dx.doi.org/10.1007/978-3-642-00834-4_22 conf/qi/2009 db/conf/qi/qi2009.html#Huertas-RoseroAR09