Majma al-Zawaid — Hadith 2572

Yazid bin al-Asamm reports from Sayyidah Maymunah (may Allah be pleased with her) (Yazid had been raised in her care as an orphan) that a miswak was always kept in a vessel, and if she was not occupied with some work or with prayer, she would take the miswak and use it.
Al-Tabarani recorded it in al-Mu'jam al-Kabir, and its narrators have been declared trustworthy. (Allamah al-Haythami says:) I say: Many hadiths about the miswak have already passed in the chapter on purification, and others will come later in the chapter on adornment, if Allah wills.