Pausanias Description of Greece 2.22.3

[3] 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.
  But I must pursue the inquiry no further. The ritual performed at the pit hard by they say was instituted by Nicostratus, a native. Even at the present day they throw into the pit burning torches in honor of the Maid who is daughter of Demeter.

[3] Now that the Tantalos 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 tomb of him who is said to be the son of Zeus and Pluto [Ploutō feminine]—it is worthy of viewing [ théā]—is on Mount Sipylos. I know because I saw it. Moreover, no constraint came upon him to flee from Sipylos, such as afterwards forced Pelops to run away when Ilus the Phrygian launched an army against him. But I must pursue the inquiry no further. The ritual performed at the pit hard by they say was instituted by Nikostratos, a native. Even at the present day they throw into the pit burning torches in honor of the Maiden who is daughter of Demeter.