Hadith 505860
Chapter 17: Zakat - كتاب الزكاة
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ يَقُولُ : لاَ تَجِبُ فِي مَالٍ زَكَاةٌ حَتَّى يَحُولَ عَلَيْهِ الْحَوْلُ .
Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to say, "Zakat does not have to be paid on property until a year has elapsed over it."
Reference Muwatta Malik 505860
USC-MSA web (English) reference : Book 17, Hadith 6