مُوَطَّأُ مَالِكٍ
Muwatta Malik 650
Fasting
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، أَنَّ أَبَا هُرَيْرَةَ، وَسَعْدَ بْنَ أَبِي وَقَّاصٍ، كَانَا يُرَخِّصَانِ فِي الْقُبْلَةِ لِلصَّائِمِ .
Yahya related to me from Malik from Zayd ibn Aslam that Abu Hurayra and Sad ibn Abi Waqqas used to say that someone who was fasting was allowed to kiss.
Arabic/English book reference: Book 18, Hadith 17