SSN ontology Issue

Hi,
I think there's the following mistake in the SSN Ontology. Into the 
ssn:Observation definition there's a restriction onProperty observedBy 
(row 155) which has been repeated twice and in different ways (the first 
time with a cardinality restriction and the second one without it):

/<rdfs:subClassOf>

<owl:Restriction>

<owl:onProperty 
rdf:resource="http://purl.oclc.org/NET/ssnx/ssn#observedBy"/>

<owl:onClass rdf:resource="http://purl.oclc.org/NET/ssnx/ssn#Sensor"/>

<owl:qualifiedCardinality 
rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger">1</owl:qualifiedCardinality>

</owl:Restriction>

</rdfs:subClassOf>

<rdfs:subClassOf>

<owl:Restriction>

<owl:onProperty 
rdf:resource="http://purl.oclc.org/NET/ssnx/ssn#observedBy"/>

<owl:allValuesFrom rdf:resource="http://purl.oclc.org/NET/ssnx/ssn#Sensor"/>

</owl:Restriction>

</rdfs:subClassOf>
/
Best regards,
Myriam