Hadith 512620
Chapter 29: Divorce - كتاب الطلاق
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ كَانَ لاَ يَعْزِلُ وَكَانَ يَكْرَهُ الْعَزْلَ .
Yahya related to me from Malik from Nafi that Abdullah ibn Umar did not practise coitus interruptus and thought that it was disapproved.
Reference Muwatta Malik 512620
USC-MSA web (English) reference : Book 29, Hadith 98