What is the traveling prayer (Du'a as-Safar)? And is there more than one prayer?

Muslim narrated from Ibn Umar that when the Prophet (peace be upon him) mounted his camel for a journey, he would say "Allahu Akbar" three times, then say: "Glory be to Him Who has subjected this to us, and we were not ourselves able to subdue it. And verily, to Our Lord we are returning. O Allah, we ask You in this journey of ours for righteousness and piety, and for deeds that You are pleased with. O Allah, lighten this journey for us and make its distance easy for us. O Allah, You are the Companion in the journey and the Guardian of the family. O Allah, I seek refuge in You from the hardships of travel, the sorrows of sights, and an evil return regarding wealth and family." And when he returned, he would add: "Returning, repenting, worshipping, and praising our Lord."