“She had heard that the first dragons had come from the east, from the Shadow Lands beyond Asshai and the islands of the Jade Sea ... Magic had died in the west when the Doom fell on Valyria and the Lands of the Long Summer, and neither spell-forged steel nor stormsingers nor dragons could hold it back, but Dany had always heard that the east was different. ... "A trader from Qarth once told me that dragons came from the moon," blonde Doreah said...”
Book:A Game of Thrones