: Optimizing_SPARQL_queries_over_disparate_RDF_data_sources_through_distributed_semi-joinshttp://purl.org/semsur/ Create a prefix for http://purl.org/semsur/ Hit Enter to save Double click to create a prefix | : subjecthttp://purl.org/SemSur/ Create a prefix for http://purl.org/SemSur/ Hit Enter to save Double click to create a prefix | Querying Distributed RDF Data Sources | : SemSur/http://purl.org/ Create a prefix for http://purl.org/ Hit Enter to save Double click to create a prefix |