Muwatta Malik 95

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنْ أَبِيهِ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ كَانَ يَقُولُ قُبْلَةُ الرَّجُلِ امْرَأَتَهُ وَجَسُّهَا بِيَدِهِ مِنَ الْمُلاَمَسَةِ فَمَنْ قَبَّلَ امْرَأَتَهُ أَوْ جَسَّهَا بِيَدِهِ فَعَلَيْهِ الْوُضُوءُ ‏.‏

Yahya related to me from Malik from Ibn Shihab from Salim ibn Abdullah that his father Abdullah ibn Umar used to say, "A man's kissing his wife and fondling her with his hands are part of intercourse. Someone who kisses his wife or fondles her with his hand must do wudu

Reference

Muwatta Malik 95

In-book

Book 2, Hadith 64