Portrait cropped from scanned encyclopedia page (grey scale corrected and Gaussain vague)
unknown, <a href="//commons.wikimedia.org/wiki/User:Siebrand" title="User:Siebrand">Siebrand</a>
<a href="//commons.wikimedia.org/wiki/File:LA2-NSRW-1-0008.jpg" title="File:LA2-NSRW-1-0008.jpg">Image:LA2-NSRW-1-0008.jpg</a>