The Mystic Marriage of Saint Catherine of Siena —
Photo Credit: By Giovanni di Paolo - Public Domain, https://commons.wikimedia.org/w/index.php?curid=1005316

The house of Saint Catherine in Siena — The house where Catherine grew up still exists.
Photo Credit: By Gryffindor - Image:House Catherine Siena Apr 2008.JPG.JPGImage:House Catherine Siena Apr 2008 (4).JPG, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4345494

St. Catherine of Siena —
Photo Credit: By Giovanni Battista Tiepolo - Public Domain, https://commons.wikimedia.org/w/index.php?curid=4892421

Thesaurus pauperum — Thesaurus pauperum. Opera noua intitulata Thesoro di poueri composta per messer Pietro Hispano. (Stampata in Vinegia : per Agostino di Bendoni, 1543 adi VI de Febraro).
Photo Credit: By Pietro Hispano - Available in the BEIC digital library and uploaded in partnership with BEIC Foundation., Public Domain, https://commons.wikimedia.org/w/index.php?curid=36512774

Palazzo San Galgano - University of Siena — The School of Humanities and Philosophy
Photo Credit: By Sailko - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=29182644

logo for University of Siena —
Photo Credit: By Source, Fair use, https://en.wikipedia.org/w/index.php?curid=40220622

Coronation of Enea Silvio Piccolomini as Pope Pius II —
Photo Credit: By Pinturicchio - Public Domain, https://commons.wikimedia.org/w/index.php?curid=15885201

Pope Pius II —
Photo Credit: By / Zeichner: unbekannt - Englische Wikipedia, Public Domain, https://commons.wikimedia.org/w/index.php?curid=5155988

Leonhard Euler — Portrait by Jakob Emanuel Handmann (1753)
Photo Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=893656

Olinde Rodrigues —
Photo Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=18352881

Iconum Insigniorum of Flavia Julia Constantia —
Photo Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=8854324