Lefteris Sidirourgos Romulo Goncalves Martin L. Kersten Niels Nes Stefan Manegold Column-store support for RDF data management: not all swans are white. 1553-1563 2008 1 PVLDB 2 http://www.vldb.org/pvldb/1/1454227.pdf db/journals/pvldb/pvldb1.html#SidirourgosGKNM08