Volume 3 · Book 27 · Hadith 5
Narrated 'Ursa bin Az-Zubair: I asked 'Aisha (whether the Prophet had performed 'Umra in Rajab). She replied, "Allah's Apostle never performed any 'Umra in Rajab."
— Sahih Bukhari, Volume 3, Book 27: Minor Pilgrammage (Umra), Hadith #5