سُنَنُ ابْنِ مَاجَهْ
Sunan Ibn Majah 267
The Book of Purification and its Sunnah
The quantity of water required for ablution and bathing from a state of sexual impurity
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا إِسْمَاعِيلُ بْنُ إِبْرَاهِيمَ، عَنْ أَبِي رَيْحَانَةَ، عَنْ سَفِينَةَ، قَالَ كَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ يَتَوَضَّأُ بِالْمُدِّ وَيَغْتَسِلُ بِالصَّاعِ .
It was narrated that Safinah said: "The Messenger of Allah used to perform ablution with a Mudd (of water) and bath with a Sa'."
Sunan Ibn Majah, 267Sahih (Darussalam)