Musnad Ahmad 27:1927

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from al-Zuhri, from Salim, from Ibn 'Umar, and from Ayyub, from Nafi', from Ibn 'Umar, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Do not prevent the female servants of Allah from praying in the mosque."