Muwatta Malik, Book 10, Hadith 12 (USC-MSA)

Yahya related to me from Malik from Abd ar-Rahman ibn al-Qasim that his father used to pray four rakas before he went to the place of prayer.

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْقَاسِمِ، أَنَّ أَبَاهُ الْقَاسِمَ، كَانَ يُصَلِّي قَبْلَ أَنْ يَغْدُوَ، إِلَى الْمُصَلَّى أَرْبَعَ رَكَعَاتٍ ‏.‏

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also referenced under: Book 10, Hadith 442 (In-Book)