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document.write('<p class="rss-item"><em>Error:</em> Feed failed! Causes may be (1) No data  found for RSS feed https://www.lehrer-online.de/rss-materialien-allgemein.xml; (2) There are no items are available for this feed; (3) The RSS feed does not validate.<br /><br /> Please verify that the URL <a href="https://www.lehrer-online.de/rss-materialien-allgemein.xml">https://www.lehrer-online.de/rss-materialien-allgemein.xml</a> works first in your browser and that the feed passes a <a href="http://feedvalidator.org/check.cgi?url=https%3A%2F%2Fwww.lehrer-online.de%2Frss-materialien-allgemein.xml">validator test</a>.</p></div>');