a crowdsourced website
... that Europol was able to identify a hotel used in child porn using Twitter and a crowdsourced website?
... that <a href="./Europol" id="mwBPE" rel="mw:WikiLink" title="Europol">Europol</a> was able to identify a hotel used in <a href="./Child_pornography" id="mwBPI" rel="mw:WikiLink" title="Child pornography">child porn</a> using Twitter and <b id="mwBPM"><a href="./Stop_Child_Abuse_–_Trace_an_Object" id="mwBPQ" rel="mw:WikiLink" title="Stop Child Abuse – Trace an Object">a crowdsourced website</a></b>?