<p>Portrait derived from <a href="//commons.wikimedia.org/wiki/File:Charles_Von_H%C3%BCgel_(1903).pdf" title="File:Charles Von Hügel (1903).pdf"><i>Charles Von Hügel, April 25, 1795 - June 2, 1870 (1903)</i></a>, a biography of the melancholic adventurer and naturalist by his son Anatole von Hügel. The caption is "CHARLES VON HÜGEL.
FROM A PHOTOGRAPH BY L. ANGERER.
</p>
<i>Vienna, 1831.".</i>
<bdi><a href="https://en.wikipedia.org/wiki/en:Ludwig_Angerer" class="extiw" title="w:en:Ludwig Angerer"><span title="Austrian photographer (1827-1879)">Ludwig Angerer</span></a>
</bdi>
19th century (photo). 1903 (book)
A copy of the book held at New York Public Library, digitised by google and made available at the Internet Archive (archive.org) at this <a rel="nofollow" class="external text" href="https://archive.org/details/charlesvonhgela00hggoog">location</a>.