Seal of John (possibly <a href="https://en.wikipedia.org/wiki/John_of_Saint_Omer" class="extiw" title="en:John of Saint Omer">John of Saint Omer</a>) of Thebes. Inscription: +S IOHANIS DE THEBIS
Original design: unknown 13th-century artist; Sketch: Gustave Schlumberger (1844–1929)
13<sup>th</sup> century <div style="display: none;">date QS:P,+1250-00-00T00:00:00Z/7</div>
Gustave Schlumberger. "Sceaux des feudataires et du clergé de l'empire latin de Constantinople". In: Bulletin Monumental, tome 62, 1897. pp. 421-458