Sahih Muslim , Hadith 318 ⓘ
'A'isha reported: When the Messenger of Allah took a bath because of sexual intercourse, he called for a vessel and took a handful of water from it and first (washed) the right side of his head, then left, and then took a handful (of water) and poured it on his head.
وَحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى الْعَنَزِيُّ، حَدَّثَنِي أَبُو عَاصِمٍ، عَنْ حَنْظَلَةَ بْنِ أَبِي سُفْيَانَ، عَنِ الْقَاسِمِ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا اغْتَسَلَ مِنَ الْجَنَابَةِ دَعَا بِشَىْءٍ نَحْوَ الْحِلاَبِ فَأَخَذَ بِكَفِّهِ بَدَأَ بِشِقِّ رَأْسِهِ الأَيْمَنِ ثُمَّ الأَيْسَرِ ثُمَّ أَخَذَ بِكَفَّيْهِ فَقَالَ بِهِمَا عَلَى رَأْسِهِ .
also referenced under: Book 3, Hadith 47 (In-Book) & Book 3, Hadith 623 (USC-MSA)