Musannaf Ibn Abi Shaybah 31283 — What they said on a man going to bed

The father of Abu Ubaydah (may Allah be pleased with him) said that when the Prophet (peace and blessings be upon him) intended to sleep, he would recite this supplication: O Allah, save me from Your punishment on the day You raise Your servants. And he (peace and blessings be upon him) would place his right hand beneath his cheek.