Maliks Muwatta Book 20, Hadith Number 264.
Section : Fasting in at-Tamattu.
Yahya related to me from Malik from Ibn Shihab from Urwa ibn az-Zubayr that A’isha umm al-muminin used to say, “Someone performing hajj at-tamattu who does not have a sacrificial animal fasts (three days) from the time he enters ihram for the hajj till the Day of Arafa, and if he does not fast then, he fasts the days of Mina.”
Yahya related to me from Malik from Ibn Shihab from Salim ibn Abdullah that Abdullah ibn Umar used to say the same concerning that, as the words of A’isha, may Allah the Exalted be pleased with her.