Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
nasai-kubra:1628 – Sūwayd b. Naṣr > ʿAbdullāh > Yūnus b. Abū Isḥāq > Muḥārib b. Dithār > al-Aswad b. Yazīd > Abū Maḥdhūrah

"Al-Aswad bin Yazid narrated to me from Abu Mahdhurah that the final words of the Adhan are: 'La ilaha illahha (there is none worthy of worship except Allah).'" (Using translation from Nasāʾī 652)   

الكبرى للنسائي:١٦٢٨ – أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَخْبَرَنَا عَبْدُ اللهِ عَنْ يُونُسَ بْنِ أَبِي إِسْحَاقَ عَنْ مُحَارِبِ بْنِ دِثَارٍ قَالَ حَدَّثَنِي الْأَسْوَدُ بْنُ يَزِيدَ عَنْ أَبِي مَحْذُورَةَ حَدَّثَهُ

«أَنَّ آخِرَ الْأَذَانِ لَا إِلَهَ إِلَّا اللهُ»  

See similar narrations below:

Collected by Nasāʾī
nasai:652 – Sūwayd > ʿAbdullāh > Yūnus b. Abū Isḥāq > Muḥārib b. Dithār > al-Aswad b. Yazīd > Abū Maḥdhūrah

"Al-Aswad bin Yazid narrated to me from Abu Mahdhurah that the final words of the Adhan are: 'La ilaha illahha (there is none worthy of worship except Allah).'"  

النسائي:٦٥٢ – أَخْبَرَنَا سُوَيْدٌ قَالَ حَدَّثَنَا عَبْدُ اللَّهِ عَنْ يُونُسَ بْنِ أَبِي إِسْحَاقَ عَنْ مُحَارِبِ بْنِ دِثَارٍ قَالَ حَدَّثَنِي الأَسْوَدُ بْنُ يَزِيدَ عَنْ أَبِي مَحْذُورَةَ

أَنَّ آخِرَ الأَذَانِ لاَ إِلَهَ إِلاَّ اللَّهُ