Musannaf Ibn Abi Shayba 36:469

Waki’ narrated to us, Sufyan narrated to us, from Abu Bakr ibn Abi al-Jahm ibn Sakhr al-Adawi, from Ubayd Allah ibn Abd Allah ibn Utbah, from Ibn Abbas, who said: The Messenger of Allah (may Allah bless him and grant him peace) performed the Fear Prayer at Dhu Qard, a land from the lands of Banu Sulaym. He arranged the people behind him in two rows: a row behind him and a row parallel to the enemy. He prayed one rak'ah with the row that was next to him. Then, those [in the first row] moved to the position of those [in the second row], and those [in the second row] moved to the position of those [in the first row], and he prayed one rak'ah with them.