Sunan Abi Dawud Book 4, Hadith 10
Ibn Umar was informed about the death of Safiyyah (the wife of the Prophet) when he was at Mecca. He proceeded till the sun set and the stars shined. He said: When the Prophet (ﷺ) was in a hurry about something while on a journey, he would combine both these prayers. He proceed till twilight had disappeared. He then combined both of them (the prayers).
They (the Companions) proceeded on the expedition of Tabuk along with the Messenger of Allah (ﷺ). He combined the noon and afternoon prayers and the sunset and night prayers. One day he delayed the prayer and came out (of his dwelling) and combined the noon and the afternoon prayers. He then went it and then came out and combined the sunset and the night prayers.
On the expedition to Tabuk if the sun had passed the meridian before the apostle of Allah (ﷺ) moved off, he combined the noon and the afternoon prayers; but if he moved off before the sun had passed the meridian, he delayed the noon prayer till he halted for the afternoon prayer. He acted similarly for the sunset prayer; if the sun set before he moved off, he combined the sunset and the night prayers, but if he moved off before sunset, he delayed the sunset prayer till he halted for the night prayer and then combined them.
Abu Dawud said: Hisham b. 'Urwah narrated this tradition from Husain b. 'Abd Allah, from Kuraib on the authority of Ibn 'Abbas from the Prophet (ﷺ) like the tradition narrated by Mufaddal and al-Laith.