Musnad Ahmad 25:733

Muhammad ibn Ja‘far narrated to us, Sa‘id narrated to us, from Ya‘la ibn Hakim, from ‘Ikrimah, from Ibn ‘Abbas, that he used to see no harm in a man getting married while he is in the state of ihram. He would say: "Indeed, the Prophet of Allah, may Allah bless him and grant him peace, married Maymunah bint al-Harith at a water [place] called Sarif, while he was in the state of ihram. Then, when the Prophet of Allah, may Allah bless him and grant him peace, finished his Hajj, he approached until, when he was at that water, he consummated the marriage with her."