مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3442
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
Abush-Sha'tha' narrated that Ibn 'Abbas told him that The Prophet (ﷺ) used to do ghusl with Maimoonah’s left-over water. `Abdur-Razzaq said: That was when I asked him about removing janabah for two people with the same water.
Musnad Ahmad 3465Its isnad is saheeh]