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SELECT ?q4 WHERE {{ ?q3 <http://ex.org/a> ?q0; ?q2 ?q1 { ?q0 <http://ex.org/c> ?q4 }} UNION {?q3 <http://ex.org/b> ?q0 . ?q0 <http://ex.org/c> ?q4 }}
Nothing to output.
Rewrite
Minimisation
Canonical Labeling
