Musnad Ahmad 30:2865

I read to Abd al-Rahman: Malik, from Abu al-Zinad, and Ishaq narrated to us, he said: Malik informed us, from Abu al-Zinad, from al-A'raj, from Abu Hurairah, that the Messenger of Allah, peace and blessings of Allah be upon him, said: "A woman and her paternal aunt shall not be joined [in marriage], nor a woman and her maternal aunt."