Musnad Ahmad 30:2318

Hassan ibn Musa narrated to us, Hammad ibn Salamah narrated to us, from Yunus ibn Ubayd, from Muhammad ibn Sirin, from Abu Hurairah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The marrow of the shins of the women of Paradise will be seen from behind the flesh."