Musnad Ahmad 31:627

'Affan narrated to us, he said: Khalid bin 'Abdullah narrated to us, Yazid bin Abi Ziyad narrated to us, from 'Abd al-Rahman bin Abi Nu'm, from Abu Sa'id al-Khudri, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Al-Hasan and Al-Husayn are the masters of the youth of the people of Paradise, and Fatimah is the mistress of their women, except for what was for Maryam bint 'Imran."