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:5396 – Abū ʿAbdullāh al-Ḥāfiẓ > Abū Bakr b. Isḥāq > Muḥammad b. Ghālib > ʿAlī b. al-Jaʿd > Shuʿbah > Manṣūr > Mujāhid > Ibn ʿAbbās

[Machine] If you travel one day into the night, then shorten the prayer.  

البيهقي:٥٣٩٦ – أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ أنبأ أَبُو بَكْرِ بْنُ إِسْحَاقَ أنبأ مُحَمَّدُ بْنُ غَالِبٍ أنبأ عَلِيُّ بْنُ الْجَعْدِ أنبأ شُعْبَةُ عَنْ مَنْصُورٍ عَنْ مُجَاهِدٍ عَنِ ابْنِ عَبَّاسٍ قَالَ

إِذَا سَافَرْتَ يَوْمًا إِلَى اللَّيْلِ فَاقْصُرِ الصَّلَاةَ