Question: How much was given in total to the Riverside Publishing vendor for educational purposes.
SPARQL:
select sum(xsd:decimal(?amount)) as ?sum from <http://linkedspending.aksw.org/dc-vendors-contractors> { ?obs qb:dataSet ls:dc-vendors-contractors. ?obs lso:dc-vendors-contractors-objecttitle <https://openspending.org/dc-vendors-contractors/objecttitle/educational>. ?obs lso:dc-vendors-contractors-to <https://openspending.org/dc-vendors-contractors/to/the-riverside-publishing>. ?obs lso:dc-vendors-contractors-amount ?amount. }