For examples, see SPARQL Examples. A basic tutorial on SPARQL is available from Apache Jena.
This endpoint (http://nomisma.org/query) supports content negotiation for the following content types with SELECT queries: text/html, text/csv, text/plain, application/sparql-results+json, and application/sparql-results+xml
text/html
text/csv
text/plain
application/sparql-results+json
application/sparql-results+xml
When querying for geo:lat and geo:long properties, a map will be generated, and geographic data may be downloaded as GeoJSON and KML.