Sahih Muslim 14002
In-book no 6725وَحَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا عَبْدَةُ، عَنْ عُبَيْدِ اللَّهِ بْنِ عُمَرَ، بِهَذَا الإِسْنَادِ وَقَالَ " ثُمَّ لْيَقُلْ بِاسْمِكَ رَبِّي وَضَعْتُ جَنْبِي فَإِنْ أَحْيَيْتَ نَفْسِي فَارْحَمْهَا " .
This hadith has been narrated on the authority of Ubaidullah b. Umar with the same chain of transmitters and he said: Then utter:" My Lord. with Thine name I place my side and if Thou keepest me alive have mercy upon myself"