"I have since discovered that the language of the people of the Inner World is much like the Sanskrit."
Jens Jansen and his son Olaf entered into the hollow portion of the Earth in 1829 in their family fishing sloop, through the Arctic opening above Zemlya and the New Siberian Islands. They remained there for two and one half years amongst the hollow earthers.
Krishna´s Jump, and the Geode Model
Ossendowski on Tibet
Maricha and Other Shapeshifters