Musnad Ahmad 33:1014

Husayn ibn Muhammad narrated to us, Muhammad ibn Mutarrif informed us, from ‘Asim ibn ‘Ubayd Allah ibn ‘Asim ibn ‘Umar ibn al-Khattab, who said: I entered upon Jabir ibn ‘Abd Allah, and the time for prayer arrived. He had garments of his upon a bed—or a clothes rack—so he stood up wrapped in his garment, then he prayed. Then he said to them when he finished: "I saw the Messenger of Allah (may Allah bless him and grant him peace) pray like this."