Sunan Abi Dawud, Hadith 5115

Narrated al-Ala' ibn al-Hadrami: Some of the children of al-Ala' ibn al-Hadrami said: Al-Ala' ibn al-Hadrami was the governor of the Prophet at al-Bahrayn, and when he wrote to him he began with his won name.

حَدَّثَنَا أَحْمَدُ بْنُ حَنْبَلٍ، حَدَّثَنَا هُشَيْمٌ، عَنْ مَنْصُورٍ، عَنِ ابْنِ سِيرِينَ، - قَالَ أَحْمَدُ قَالَ مَرَّةً يَعْنِي هُشَيْمًا - عَنْ بَعْضِ وَلَدِ الْعَلاَءِ أَنَّ الْعَلاَءَ بْنَ الْحَضْرَمِيِّ كَانَ عَامِلَ النَّبِيِّ صلى الله عليه وسلم عَلَى الْبَحْرَيْنِ فَكَانَ إِذَا كَتَبَ إِلَيْهِ بَدَأَ بِنَفْسِهِ ‏.‏

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also referenced under: Hadith 5134 (DarusSalam)