Nikos Bikakis Nektarios Gioldasis Chrisa Tsinaraki Stavros Christodoulakis Querying XML Data with SPARQL. 372-381 2009 DEXA http://dx.doi.org/10.1007/978-3-642-03573-9_32 conf/dexa/2009 db/conf/dexa/dexa2009.html#BikakisGTC09