حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، كَانَ يَقُولُ اللَّهُمَّ إِنِّي أَسْأَلُكَ شَهَادَةً فِي سَبِيلِكَ وَوَفَاةً بِبَلَدِ رَسُولِكَ ‏.‏

Yahya related to me from Malik from Zayd ibn Aslam that Umar ibnal-Khattab used to say, "O Allah! I ask you for martyrdom in Your wayand death in the city of Your Messenger!" Translation Not Available

Book Ref: Muwatta Imam Malik Book 21 Hadith 995
Web Ref:  Muwatta Imam Malik Book 21 Hadith 34