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.
bukhari:4171Isḥāq > Yaḥyá b. Ṣāliḥ > Muʿāwiyah > Ibn Salāam > Yaḥyá > Abū Qilābah > Thābit b. al-Ḍaḥḥāk

that Thabit bin Ad-Dahhak had informed him that he was one of those who had given the Pledge of allegiance (of Al-Hudaibiya) beneath the Tree.  

البخاري:٤١٧١حَدَّثَنَا إِسْحَاقُ حَدَّثَنَا يَحْيَى بْنُ صَالِحٍ قَالَ حَدَّثَنَا مُعَاوِيَةُ هُوَ ابْنُ سَلاَّمٍ عَنْ يَحْيَى عَنْ أَبِي قِلاَبَةَ أَنَّ ثَابِتَ بْنَ الضَّحَّاكِ

أَخْبَرَهُ أَنَّهُ بَايَعَ النَّبِيَّ ﷺ تَحْتَ الشَّجَرَةِ