Count the different affiliations of the authors of 'The Entity Registry System From concept to deployment'.
How many different affiliations do the authors of 'The Entity Registry System From concept to deployment' have?
SELECT (COUNT(DISTINCT ?answer) AS ?count) WHERE { <https://dblp.org/rec/journals/corr/Gramada16> <https://dblp.org/rdf/schema#authoredBy> ?x . ?x <https://dblp.org/rdf/schema#primaryAffiliation> ?answer }
<https://dblp.org/rec/journals/corr/Gramada16>