Yahya related to me from Malik from Nafi that Abdullah ibn Umar never used to pray anything with the fard prayer, either before it or after it, while travelling, except in the depths of the night. He would pray on the ground or on his mount, whichever way it was facing.  

أَنَّهُ لَمْ يَكُنْ يُصَلِّي مَعَ صَلاَةِ الْفَرِيضَةِ فِي السَّفَرِ شَيْئًا قَبْلَهَا وَلاَ بَعْدَهَا إِلاَّ مِنْ جَوْفِ اللَّيْلِ فَإِنَّهُ كَانَ يُصَلِّي عَلَى الأَرْضِ وَعَلَى رَاحِلَتِهِ حَيْثُ تَوَجَّهَتْ  

Yahya related to me from Malik that he had heard that al-Qasim ibn Muhammad and Urwa ibn az-Zubayr and Abu Bakr ibn Abd ar Rahman used to pray nawafil when travelling. Yahya said that Malik was asked about voluntary prayers when travelling and he said, "There is no harm in them, either at night or during the day. I have heard that some of the people of knowledge used to do that."  

أَنَّ الْقَاسِمَ بْنَ مُحَمَّدٍ وَعُرْوَةَ بْنَ الزُّبَيْرِ وَأَبَا بَكْرِ بْنَ عَبْدِ الرَّحْمَنِ كَانُوا يَتَنَفَّلُونَ فِي السَّفَرِ قَالَ يَحْيَى وَسُئِلَ مَالِكٌ عَنِ النَّافِلَةِ فِي السَّفَرِ فَقَالَ لاَ بَأْسَ بِذَلِكَ بِاللَّيْلِ وَالنَّهَارِ وَقَدْ بَلَغَنِي أَنَّ بَعْضَ أَهْلِ الْعِلْمِ كَانَ يَفْعَلُ ذَلِكَ  

Yahya related to me that Malik said, "I have heard from Nafi that Abdullah ibn Umar used to see his son, Ubaydullah ibn Abdullah, doing voluntary prayers on a journey,and he would not disapprove of it."  

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ كَانَ يَرَى ابْنَهُ عُبَيْدَ اللَّهِ بْنَ عَبْدِ اللَّهِ يَتَنَفَّلُ فِي السَّفَرِ فَلاَ يُنْكِرُ عَلَيْهِ  

Yahya related to me from Malik from Amr ibn Yahya al-Mazini from Abu'l-Hubab Said ibn Yasar that Abdullah ibn Umar said, "I saw the Messenger of Allah ﷺ praying on a donkey while heading towards Khaybar."  

أَنَّهُ قَالَ رَأَيْتُ رَسُولَ اللَّهِ ﷺ يُصَلِّي وَهُوَ عَلَى حِمَارٍ وَهُوَ مُتَوَجِّهٌ إِلَى خَيْبَرَ  

Yahya related to me from Malik from Abdullah ibn Dinar from Abdullah ibn Umar that the Messenger of Allah ﷺ used to pray on his mount while travelling, whichever way it was facing. Abdullah ibn Dinar said, "Abdullah ibn Umar would also do that."  

أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يُصَلِّي عَلَى رَاحِلَتِهِ فِي السَّفَرِ حَيْثُ تَوَجَّهَتْ بِهِ قَالَ عَبْدُ اللَّهِ بْنُ دِينَارٍ وَكَانَ عَبْدُ اللَّهِ بْنُ عُمَرَ يَفْعَلُ ذَلِكَ  

Yahya related to me from Malik that Yahya ibn Said said, "I saw Anas ibn Malik on a journey praying on a donkey facing away from the qibla. He did the raka and the sajda by motioning with his head, without putting his face on anything."  

قَالَ رَأَيْتُ أَنَسَ بْنَ مَالِكٍ فِي السَّفَرِ وَهُوَ يُصَلِّي عَلَى حِمَارٍ وَهُوَ مُتَوَجِّهٌ إِلَى غَيْرِ الْقِبْلَةِ يَرْكَعُ وَيَسْجُدُ إِيمَاءً مِنْ غَيْرِ أَنْ يَضَعَ وَجْهَهُ عَلَى شَىْءٍ