Musannaf Ibn Abi Shayba 21:309

Muhammad ibn Fudayl narrated to us, from ‘Asim, from Thabit al-Bunani, who said: A man from the companions of Muhammad (may Allah bless him and grant him peace) narrated to me at this pillar, saying: Whoever says, "Subhan Allah wa bihamdihi, astaghfirullah wa atubu ilayh" (Glory be to Allah and by His praise, I seek forgiveness from Allah and I repent to Him), it is written for him on a parchment, then a seal of musk is placed upon it. It is not broken until he is brought with it on the Day of Resurrection.