Musannaf Ibn Abi Shayba 3:2399

Waki’ narrated to us, he said: Sufyan narrated to us, from Ibn al-Fadl, from al-Hasan, he said: If he forgets a prayer while in residence and remembers it while traveling, he performs the prayer of residence. And if he forgets a prayer while traveling and remembers it while in residence, he performs the prayer of travel.