Musnad Ahmad Hadith 19865

A young man asked Imran bin Husain (may Allah be pleased with him) about the prayer of the Prophet (ﷺ) during travel, so he turned towards the gathering and said, "This young man is asking me about the prayer of the Prophet (ﷺ) during travel, so you all should also remember it well. Whenever the Prophet (ﷺ) traveled, he performed two rak'ahs until his return, and on the occasion of the conquest of Makkah, the Prophet (ﷺ) stayed in Makkah for eighteen days but continued to lead the people in two rak'ahs." Imran bin Husain (may Allah be pleased with him) narrated the previous hadith from Yunus bin Muhammad with this addition: "However, he did not shorten the Maghrib prayer, then he would say, 'O people of Makkah! You stand up and complete the remaining two rak'ahs yourselves because we are travelers.' After that, the Prophet (ﷺ) went for the expeditions of Hunayn and Ta'if and continued to perform two rak'ahs, then went to Ji'ranah and in the month of Dhu al-Qa'dah assumed the ihram for 'Umrah (and did the same). Then I participated in the expeditions, Hajj, and 'Umrah journeys with Abu Bakr as-Siddiq (may Allah be pleased with him), and he also performed two rak'ahs. Then I also prayed in the same way with Uthman (may Allah be pleased with him) in the early period of his caliphate, but later Uthman (may Allah be pleased with him) started performing four rak'ahs."