Musnad Abu Ya'la al-Mawsili 150:190

Abu Kurayb narrated to us, Hammad bin Khalid narrated to us, from Abdullah bin Umar, from Ubaydullah bin Umar, from al-Qasim, from Aisha, who said: The Messenger of Allah (may Allah bless him and grant him peace) was asked about a man who sees in a dream that he has had a wet dream, but does not see any wetness. He said: "There is no ghusl (ritual bath) upon him." Umm Sulaym said: "O Messenger of Allah, and if a woman sees that?" He said: "Women are the counterparts of men."