Hadith 506600
Chapter 18: Fasting - كتاب الصيام
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، أَنَّهُ كَانَ يُسَافِرُ فِي رَمَضَانَ وَنُسَافِرُ مَعَهُ فَيَصُومُ عُرْوَةُ وَنُفْطِرُ نَحْنُ فَلاَ يَأْمُرُنَا بِالصِّيَامِ .
Yahya related to me from Malik that Hisham ibn Urwa said, "My father, Urwa, used to travel in Ramadan, and we would travel with him, and he used to fast while we would break the fast, and he would not tell us to fast."
Reference Muwatta Malik 506600
USC-MSA web (English) reference : Book 18, Hadith 26