حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، 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 from Nafi that Abdullah ibn Umarnever used to pray anything with the fard prayer, either before it orafter it, while travelling, except in the depths of the night. Hewould pray on the ground or on his mount, whichever way it was facing. Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 353
Web Ref:  Muwatta Imam Malik Book 9 Hadith 24