بُلُوغُ الْمَرَامِ
Bulugh al-Maram 302
The Book of Prayer
وَعَنْ اِبْنِ عَبَّاسٍ -رَضِيَ اَللَّهُ عَنْهُمَا- أَنَّ اَلنَّبِيَّ - صلى الله عليه وسلم -كَانَ يَقُولُ بَيْنَ اَلسَّجْدَتَيْنِ : { اَللَّهُمَّ اِغْفِرْ لِي , وَارْحَمْنِي , وَاهْدِنِي , وَعَافِنِي , وَارْزُقْنِي } رَوَاهُ اَلْأَرْبَعَةُ إِلَّا النَّسَائِيُّ , وَاللَّفْظُ لِأَبِي دَاوُدَ , وَصَحَّحَهُ اَلْحَاكِمُ . [1]
Narrated Ibn 'Abbas (RA): The Prophet (ﷺ) used to say between the two prostrations: "Allahumma ighfir li, warhamni, wahdini, wa 'afini, warzuqni (O Allah, forgive me, have mercy on me, guide me, grant me health and well-being, and provide sustenance for me)." [Reported by al-Arba'a except An-Nasa'i, and this is the wording of Abu Dawud. Al-Hakim graded it Sahih (authentic)].
Sunnah.com reference: Book 2, Hadith 188