Norton: http://safeweb.norton.com/report/show?url=lanke.historielag.org
Sucuri: http://sitecheck.sucuri.net/scanner/?scan=http%3A%2F%2Flanke.historielag.org%2F
Virustotal: https://www.virustotal.com/en/url/def2bd0ea6652830334f9ad642dda580b754dfdd53f4f43d601dce3012075279/analysis/1376409774/
Comodo: http://app.webinspector.com/public/reports/16323454
URLQuery: http://urlquery.net/report.php?id=4532857

Looks clean. You can report a false positive here: http://www.avast.com/contact-form.php

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