Attributions:
Photo 1: by Wolfgang Stuck,
public domain,
https://commons.wikimedia.org/w/index.php?curid=446912
Photo 2: by MM, public domain, https://commons.wikimedia.org/w/index.php?curid=163425
Photo 3: by
Diliff - Own work, CC BY-SA 2.5,
https://commons.wikimedia.org/w/index.php?curid=2067974
Photo 4: by Annibale Carracci, public domain, https://commons.wikimedia.org/w/index.php?curid=39990977