Musnad Ahmad 939:2

Isma'il narrated to us, from 'Abd al-Rahman ibn Ishaq, from Muhammad ibn 'Abd Allah ibn 'Amr ibn Hisham, from Busr ibn Sa'id, from Zayd ibn Khalid al-Juhani, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Do not prevent the female servants of Allah from the mosques, and let them go out while they are not perfumed."