SILK Issue - Configuration XML

<Silk>
  <Prefixes>
    <Prefix id="rdf" namespace="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/>
    <Prefix id="rdfs" namespace="http://www.w3.org/2000/01/rdf-schema#"/>
    <Prefix id="geo" namespace="http://www.opengis.net/ont/geosparql#"/>
    <Prefix id="geosf" namespace="http://www.opengis.net/ont/sf#"/>
  </Prefixes>
  <DataSources>
    <Dataset id="nuts" type="file">
      <Param name="file" value="nuts.nt"/>
      <Param name="format" value="N-TRIPLES"/>
    </Dataset>
    <Dataset id="clc" type="file">
      <Param name="file" value="clc.nt"/>
      <Param name="format" value="N-TRIPLES"/>
    </Dataset>
  </DataSources>
  <Interlinks>
    <Interlink id="nuts-clc">
      <SourceDataset dataSource="nuts" var="a">
          <RestrictTo>
            ?a ?p ?q .
          </RestrictTo>
      </SourceDataset>
      <TargetDataset dataSource="clc" var="b">
          <RestrictTo>
            ?b rdf:type geosf:Polygon .
          </RestrictTo>
      </TargetDataset>
      <LinkageRule linkType="geo:sfEquals">
          <Compare id="aunnamed_6" required="true" weight="1" metric="SEqualsMetric" threshold="1.0">
              <TransformInput id="aunnamed_8" function="GeometryTransformer">
                <Input id="aunnamed_1" path="?a/geo:asWKT"/>
              </TransformInput>
              <TransformInput id="aunnamed_9" function="GeometryTransformer">
                <Input id="aunnamed_2" path="?b/geo:asWKT"/>
              </TransformInput>
              <Param name="blockingParam" value="10.0"/>
          </Compare>
        <Filter/>
      </LinkageRule>
    </Interlink>
  </Interlinks>
  <Outputs>
    <Dataset id="clc" type="file">
      <Param name="file" value="links.nt"/>
      <Param name="format" value="N-TRIPLE"/>
    </Dataset>
  </Outputs>
</Silk>