Hadith 501190
Chapter 2: Purity - كتاب الطهارة
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ يَعْرَقُ فِي الثَّوْبِ وَهُوَ جُنُبٌ ثُمَّ يُصَلِّي فِيهِ .
Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to sweat in a garment while he was junub and then pray with it on.
Reference Muwatta Malik 501190
USC-MSA web (English) reference : Book 2, Hadith 89