Reference : Hisn al-Muslim 30

اللّهُـمَّ رَبَّ جِـبْرائيل ، وَميكـائيل ، وَإِسْـرافيل، 
فاطِـرَ السَّمواتِ وَالأَرْض ،
عالـِمَ الغَيْـبِ وَالشَّهـادَةِ 
أَنْـتَ تَحْـكمُ بَيْـنَ عِبـادِكَ فيـما كانوا فيهِ يَخْتَلِفـون. 
اهدِنـي لِمـا اخْتُـلِفَ فيـهِ مِنَ الْحَـقِّ بِإِذْنِك ،
إِنَّـكَ تَهْـدي مَنْ تَشـاءُ إِلى صِراطٍ مُسْتَقـيم
Allāhumma, rabba Jibrā'īla, wa Mīkā'īla, wa Isrāfīla 
Fāṭira 's-samāwāti wa 'l-arḍi, `
ālima 'l-ghaybi wa 'sh-shahādati, 
anta taḥkumu bayna `ibādika fīmā kānū fīhi yakhtalifūna. 
Ihdinī li makhtulifa fīhi min al-ḥaqqi bi idhnika. 
Innaka tahdī man tashā'u ilā ṣirāṭin mustaqīm.

O Allah, Lord of Jibraīl, Mīkaīl and Israfīl (great angels),
Creator of the heavens and the Earth, 
Knower of the seen and the unseen. 
You are the arbitrator between Your servants in that which they have disputed. 
Guide me to the truth by Your leave, in that which they have differed, 
for verily You guide whom You will to a straight path."

Reference:
Muslim 1/534

Chapter: At the start of the prayer (after takbeer)