Musnad Ahmad 1153:369

Yunus narrated to us, Hammad—meaning Ibn Zayd—narrated to us, from Abu Hashim, the owner of the pomegranates, from Abu Mijlaz, from al-Harith ibn Nawfal, from Aisha, that she was asked about seminal fluid (janabah). She said: "I used to rub the seminal fluid from the garment of the Messenger of Allah, may Allah bless him and grant him peace."