Louis I of Spain —
Photo Credit: By Jean Ranc, Public Domain, https://commons.wikimedia.org/w/index.php?curid=7685013

Charles II of Spain —
Photo Credit: By Juan Carreño de Miranda - Kunsthistorisches Museum Wien, Bilddatenbank., Public Domain, https://commons.wikimedia.org/w/index.php?curid=4601818

Philip IV of Spain —
Photo Credit: By Diego Velázquez - Public Domain, https://commons.wikimedia.org/w/index.php?curid=18176787

Philip III of Spain —
Photo Credit: By Andrés López Polanco - Kunsthistorisches Museum Wien, Bilddatenbank., Public Domain, https://commons.wikimedia.org/w/index.php?curid=4645489

Felipe V de España —
Photo Credit: By Louis-Michel van Loo - Public Domain, https://commons.wikimedia.org/w/index.php?curid=7683986

Portrait of Charles III — Anton Raphael Mengs, ca. 1765
Photo Credit: Public Domain, https://commons.wikimedia.org/w/index.php?curid=4727473

John Paul Jones —
Photo Credit: By Charles Willson Peale - Public Domain, https://commons.wikimedia.org/w/index.php?curid=9753295

Vitalik announcing Ethereum — Ethereum’s public announcement at The North American Bitcoin Conference in Miami, Florida, USA - January 25, 2014
Photo Credit: Marc van der Chijs - https://blog.ethereum.org/2016/02/09/cut-and-try-building-a-dream

Gavin Wood contacts Vitalik Buterin —
Photo Credit: https://vitalik.ca/general/2017/09/14/prehistory.html

Aerial view of the University of Kiel central campus —
Photo Credit: By Klaas Ole Kürtz (Drbashir117) - Own work, CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=84102

Seal of the University of Kiel —
Photo Credit: By University of Kiel - Public Domain, https://commons.wikimedia.org/w/index.php?curid=71284817