Yes, the original song "Ti ine afto pou to lene agapi" ("What is this thing they call love") is sung by Sophia Loren and Tonis Maroudas. Yup, like Ypnos has already mentioned, it's in Greek, from the soundtrack of the movie "To pedi ke to delfini" (1957).
All other English and Greek versions are covers, including the Julie London one. It has been performed also by Harry Belafonte, Nana Mouskouri, Giannis Parios, Haris Alexiou and so on.
No, mwro mou, it's not a traditional song. The music is written by Takis Morakis.
The English lyrics, written by Paul Francis Webster, go like this (or at least Julie London's version, which I happen to have):
There's a tale that they tell of a dolphin
And a boy made of gold
With the shells and the pearls in the deep
He has lain many years fast asleep
What they tell of the boy on a dolphin
Who can say if it's true
Should he rise from the depths of the ocean
Any wish that you wish may come true
You say he is only a statue
And what can a statue achieve
And yet while I'm gazing at you
My heart tells my head to believe
If the boy whom the gods have enchanted
Should arise from the sea
And the wish of my heart could be granted
I would wish that you loved only me
***
As you can see, they have nothing to do with the Greek lyrics, written by Giannis Fermanoglou.
