Hadith 5:71
‘Abd ar-Rahman b. ‘Auf reported God’s messenger as saying, “One who fasts in Ramadan while travelling is like one who breaks his fast when not travelling.” Ibn Majah transmitted it.
وَعَنْ عَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «صَائِمُ رَمَضَانَ فِي السَّفَرِ كَالْمُفْطِرِ فِي الْحَضَرِ» . رَوَاهُ ابْن مَاجَه
Original Reference: Mishkat al-Masabih 2028