Musnad Ahmad 1153:926

'Affan narrated to us, he said: Khalid ibn al-Harith narrated to me, he said: Ash'ath narrated to us, from al-Hasan, from Sa'd ibn Hisham, from 'Aishah, "That the Messenger of Allah, peace and blessings of Allah be upon him, forbade at-tabattul (celibacy)."