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
bayhaqi:2588 – ʿUmar b. ʿAbd al-ʿAzīz b. ʿUmar b. Qatādah > Abū al-Faḍl b. Khamīrawayh > Aḥmad b. Najdah > Saʿīd b. Manṣūr > Ibrāhīm b. Saʿd b. Ibrāhīm > Ibn Shihāb

[Machine] Ibn Umar and Zaid bin Thabit used to say the takbir and perform the ruku' when they come to the imam while he is in the ruku' position.  

البيهقي:٢٥٨٨ – أَخْبَرَنَا عُمَرُ بْنُ عَبْدِ الْعَزِيزِ بْنِ عُمَرَ بْنِ قَتَادَةَ أنبأ أَبُو الْفَضْلِ بْنُ خَمِيرَوَيْهِ ثنا أَحْمَدُ بْنُ نَجْدَةَ ثنا سَعِيدُ بْنُ مَنْصُورٍ ثنا إِبْرَاهِيمُ بْنُ سَعْدِ بْنِ إِبْرَاهِيمَ عَنِ ابْنِ شِهَابٍ قَالَ

كَانَ ابْنُ عُمَرَ وَزَيْدُ بْنُ ثَابِتٍ إِذَا أَتَيَا الْإِمَامَ وَهُوَ رَاكِعٌ كَبَّرَا تَكْبِيرَةً وَيَرْكَعَانِ بِهَا