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
muslim:583a – Zuhayr b. Ḥarb > Sufyān b. ʿUyaynah > ʿAmr > Bidhā Abū Maʿbad Thum Ankarah Baʿd > Ibn ʿAbbās

We used to know that Messenger of Allah ﷺ had finished his prayer when we heard the takbir (Allah-O-Akbar).  

مسلم:٥٨٣a – حَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ عَنْ عَمْرٍو قَالَ

أَخْبَرَنِي بِذَا أَبُو مَعْبَدٍ ثُمَّ أَنْكَرَهُ بَعْدُ عَنِ ابْنِ عَبَّاسٍ قَالَ كُنَّا نَعْرِفُ انْقِضَاءَ صَلاَةِ رَسُولِ اللَّهِ ﷺ بِالتَّكْبِيرِ