Hollow Earth - Wikipedia

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Richard E. Byrd - Wikipedia

26 Hollow Earth. ideas earth, earth's core, outer core

The Secret Lost Diary of Admiral Richard E. Byrd and The Phantom of the Poles: 9781606111376: Byrd, Admiral Richard E., Beckley, Timothy Green, Reed, William, X, Commander, Swartz, Tim R: Books

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A danish buffoon and the hollow earth: Niels Klim's Adventure

Where did the myth of a hollow Earth come from? - Quora

Firmament - Wikipedia

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Kong: Skull Island - Wikipedia