Pausanias: Now that the Tantalus is buried here who was the son of Thyestes or Broteas (both accounts are given) and married Clytaemnestra before Agamemnon did, I will not gainsay; but the grave of him who legend says was son of Zeus and Pluto—it is worth seeing—is on Mount Sipylus. I know because I saw it. Moreover, no constraint came upon him to flee from Sipylus, such as afterwards forced Pelops to run away when Ilus the Phrygian launched an army against him.
Pausanias, Description of Greece II.22.3 - http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0160%3Abook%3D2%3Achapter%3D22%3Asection%3D3Copied