وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ يَقْصُرُ الصَّلاَةَ فِي مَسِيرِهِ الْيَوْمَ التَّامَّ ‏.‏

Yahya related to me from Malik from Ibn Shihab from Salim ibnAbdullah that Abdullah ibn Umar used to shorten the prayer when hetravelled for a whole day. Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 343
Web Ref:  Muwatta Imam Malik Book 9 Hadith 15