Jami at-Tirmidhi Hadith 950

Ibn Umar said: When the Prophet would come home from a battle, or Hajj, or Umrah, when he was it a tract of land or raised area he would say 'Allahu Akbar (Allah is Most Great)' three times, then say: 'La Ilaha illallah Wahdahu la sharika lahu, lahul-mulku wa lahul-Hamdu wa Huwa ala kulli shai'in qadir. A'ibuna ta'ibun abidun saa'ihuna li Rabbina Hamiduna, Sadaqallahu wa'dahu wa nasara abdahu wa hazamal-ahzab Wahdah. (None has the right to be worshiped but Allah Alone without partners. To Him belongs the sovereignty and to Him belongs the praise, and He has power over all things. We are returning, repenting, worshipping, traveling for our Lord, and we are praising. Allah has told the truth, and kept His promise and helped His worshipper, and routed the confederates, Alone.'