Sahih Bukhari
Agriculture
Volume: 003 / Book Number: 039 / Hadith Number: 530
Narrated 'Umar:
While the Prophet was in Al-'Aqiq he said, "Someone (meaning Gabriel) came to me from my Lord tonight (in my dream) and said, 'Offer the prayer in this blessed valley and say (I intend to perform) Umra along with Hajj (together).' "