Why does the tower of Pisa lean? By BBC Earth Lab (video).
Original title: "Why does the leaning tower of Pisa lean? | Sci Guide with Jheni Osman | Head Squeeze" (17/11/2013).
YouTube channel: BBC Earth Lab.
Haga clic en el enlace https://youtu.be/trZgC8icFVU para abrir el recurso.