"I asked Salim bin 'Abdullah about how his father prayed when traveling. We asked him: 'Did he combine any of his prayers when traveling?' He said that Safiyyah bint Abi 'Ubaid was married to him, and she wrote to him, when he was at some farmland of his, saying: 'This is the last of my days in this world, and the first day of the Hereafter." [1] He rode quickly to go to her, and when the time for Zuhr came, the Mu'adhdhin said to him: "The prayer, O Abu 'Abdur-Rahman!" But he paid no attention to him until it was between the time for the two prayers, then he stopped and said: "Say the Iqamah and when I say the Taslim, say the Iqamah." Then he rode on again, and when the sun set the Mu'adhdhin said to him; "The prayer!" He said: "Do as you did for Zuhr and 'Asr." When the stars had appeared, he stopped and said to the Mu'adhdhin: "Say the Iqamah and when I say the Taslim, say the Iqamah." He prayed, then when he had finished he turned to us and said: "The Messenger of Allah ﷺ said: 'If any one of you has an urgent need that he fears he may miss, let him pray like this.'" [1] Meaning that she was dying. (Using translation from Nasāʾī 588)  

عَنْ صَلَاةِ أَبِيهِ فِي السَّفَرِ وَسَأَلْنَاهُ هَلْ كَانَ يَجْمَعُ بَيْنَ شَيْءٍ مِنْ صَلَاتِهِ فِي سَفَرٍ؟ فَذَكَرَ أَنَّ صَفِيَّةَ بِنْتَ أَبِي عُبَيْدٍ وَكَانَتْ تَحْتَهُ كَتَبَتْ إِلَيْهِ وَهُوَ فِي زِرَاعَةٍ لَهُ إِنِّي فِي آخِرِ يَوْمٍ مِنَ الدُّنْيَا وَأَوَّلِ يَوْمٍ مِنَ الْآخِرَةِ فَرَكِبَ فَأَسْرَعَ السَّيْرَ حَتَّى إِذَا حَانَتْ صَلَاةُ الظُّهْرِ قَالَ لَهُ الْمُؤَذِّنُ الصَّلَاةَ يَا أَبَا عَبْدِ الرَّحْمَنِ فَلَمْ يَلْتَفِتْ حَتَّى إِذَا كَانَ بَيْنَ الصَّلَاتَيْنِ نَزَلَ فَقَالَ أَقِمْ فَإِذَا سَلَّمْتُ فَأَقِمْ فَصَلَّى ثُمَّ رَكِبَ حَتَّى إِذَا غَابَتِ الشَّمْسُ قَالَ لَهُ الْمُؤَذِّنُ الصَّلَاةَ قَالَ كَفِعْلِكَ لِصَلَاةِ الظُّهْرِ وَالْعَصْرِ ثُمَّ سَارَ حَتَّى إِذَا اشْتَبَكَتِ النُّجُومُ نَزَلَ ثُمَّ قَالَ لِلْمُؤَذِّنِ أَقِمْ فَإِذَا سَلَّمْتُ فَأَقِمْ فَصَلَّى ثُمَّ انْصَرَفَ ثُمَّ الْتَفَتَ إِلَيْنَا فَقَالَ قَالَ رَسُولُ اللهِ ﷺ «إِذَا حَفَزَ أَحَدَكُمُ الْأَمْرُ الَّذِي يَخَافُ فَلْيُصَلِّ هَذِهِ الصَّلَاةَ»  

It was narrated from Ibn 'Abbas that he prayed Al-Uula (Zuhr) and 'Asr together in Al-Basrah with nothing in between them, and he prayed Maghrib and 'Isha' together with nothing in between them. He did that because he was busy and Ibn 'Abbas said that he had prayed Zuhr and 'Isha' together with the Messenger of Allah ﷺ in Al-Madinah, eight Rak'ahs with nothing in between. (Using translation from Nasāʾī 590)  

أَنَّهُ صَلَّى مَعَ رَسُولِ اللهِ ﷺ بِالْمَدِينَةِ الْأُولَى وَالْعَصْرَ ثَمَانِيَ سَجَدَاتٍ لَيْسَ بَيْنَهُمَا شَيْءٌ