Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: The Prophet (peace and blessings be upon him) used to offer two prayers together during a journey.
Abu Ya'la, Imam al-Bazzar and Imam al-Tabarani in al-Mu'jam al-Kabir recorded it; the narrators of Abu Ya'la are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2966