Maliks Muwatta Book 20, Hadith Number 57.
Section : Umra in the Months of Hajj.
Yahya related to me from Malik from Hisham ibn Urwa, from his father, that the Messenger of Allah, may Allah bless him and grant him peace, only did three umras, one of them in Shawwal, and two in Dhu’l-Qada.