I'm sure with a 100% confidence that the scene in #TheBoyAndTheHeron where the large space-ship shaped rock floating in the sky over the hill is introduced is a reference to something similar, but I can't put my finger on what it's a reference to (to wit, the sunken ship with the trees where young Kiriko lives is obviously a reference to Böcklin's #DieToteninsel —the #IslandOfTheDead). Anybody can help me with the floating rock in the sky reference?