(10) باب الْقَدْرِ الْمُسْتَحَبِّ مِنَ الْمَاءِ فِي غُسْلِ الْجَنَابَةِ وَغُسْلِ الرَّجُلِ وَالْمَرْأَةِ فِي إِنَاءٍ وَاحِدٍ فِي حَالَةٍ وَاحِدَةٍ وَغُسْلِ أَحَدِهِمَا بِفَضْلِ الآخَرِ
'A'isha reported:
I and the Messenger of Allah (ﷺ) took a bath from one vessel which was placed between me and him and he would get ahead of me, so that I would say: Spare (some water for) me, spare (some water for) me; and she said that they had had sexual intercourse.
Reference: Sahih Muslim 321 d
In-book reference: Book 3, Hadith 54
USC-MSA web (English) reference(deprecated numbering scheme): Book 3, Hadith 630