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I've only just discovered this resource, but the International Institute
of Social History in the Netherlands contains, <i>inter alia</i>,
archives of <br>
the Algemeyner Yidisher Arbeyter Bund:<br><br>
<pre>
<a href="http://www.iisg.nl/archives/en/files/a/10739029.php" eudora="autourl">
http://www.iisg.nl/archives/en/files/a/10739029.php
</a></pre>If you do two searches, one on Esperanto, the other on
Zamenhof, (and perhaps you will find more stuff by using other
keywords)you will find holdings in several archives. Note for example
this archive:<br>
Archief Federacio de Laboristaj Esperantistoj (Amsterdam)<br>
<a href="http://search.iisg.nl/search/search?action=transform&col=archives&xsl=archives-detail.xsl&lang=en&docid=10729125_EAD" eudora="autourl">
http://search.iisg.nl/search/search?action=transform&col=archives&xsl=archives-detail.xsl&lang=en&docid=10729125_EAD<br>
<br>
</a>I haven't had time to explore this resource, but interested
historically-oriented persons should know about it.<br><br>
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