Count the different affiliations of the authors of 'Recursive linear estimation for general discrete-time descriptor systems'.
How many different affiliations do the authors of 'Recursive linear estimation for general discrete-time descriptor systems' have?
SELECT (COUNT(DISTINCT ?answer) AS ?count) WHERE { <https://dblp.org/rec/journals/automatica/IshiharaTB10> <https://dblp.org/rdf/schema#authoredBy> ?x . ?x <https://dblp.org/rdf/schema#primaryAffiliation> ?answer }
<https://dblp.org/rec/journals/automatica/IshiharaTB10>