Seal of John, <a href="https://en.wikipedia.org/wiki/Latin_Archbishop_of_Patras" class="extiw" title="en:Latin Archbishop of Patras">Latin Archbishop of Patras</a>. Inscription: [S] IOHANN[IS ARCIEPISC.] PATRA[CENSIS]
Original design: unknown 13th-century artist; Sketch: Gustave Schlumberger (1844–1929)
1304
Gustave Schlumberger. "Sceaux des feudataires et du clergé de l'empire latin de Constantinople". In: Bulletin Monumental, tome 62, 1897. pp. 421-458