Musannaf Ibn Abi Shayba 9:1048

Ya'la ibn 'Ubayd narrated to us, from Muhammad ibn Bakr, from 'Abd al-Malik ibn Abi Bakr ibn 'Abd al-Rahman ibn al-Harith ibn Hisham, from his father, from Umm Salamah: That the Messenger of Allah (may Allah bless him and grant him peace), when he married Umm Salamah, stayed with her for three [days]. And he said to her: "It is not the case that you have any insignificance before your family. If you wish, I will stay with you for seven [days], and if I stay with you for seven [days], I will stay with [each of] my wives for seven [days]."