@prefix ex:  <http://www.w3.org/2009/sparql/docs/tests/data-sparql11/negation#> .
@prefix dc:  <http://purl.org/dc/elements/1.1/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

ex:examination1 a ex:PhysicalExamination;
                dc:date "2010-01-10"^^xsd:date ;
                ex:precedes ex:operation1 ;
                ex:follows ex:examination2  .
ex:operation1   a ex:SurgicalProcedure;
                dc:date "2010-01-15"^^xsd:date;
                ex:follows ex:examination1, ex:examination2 .
ex:examination2 a ex:PhysicalExamination;
                dc:date "2010-01-02"^^xsd:date;
                ex:precedes ex:operation1, ex:examination1 .