Musannaf Ibn Abi Shayba 1:1348

Isma'il ibn 'Ulayyah narrated to us, from Ayyub, from Sulayman ibn Yasar, that Fatima bint Abi Hubaysh experienced prolonged menstrual bleeding (istihada), so she asked the Prophet, may Allah bless him and grant him peace, or it was asked on her behalf. He commanded her to leave the prayer during the days of her (usual) menstrual cycle, then to perform ghusl (ritual bath) for what is other than that, then to bind herself with a cloth and pray.