It was narrated that Khawlah bin Hakim said:
"I asked the Messenger of Allah (ﷺ) about a woman who has a wet dream and he said: 'If she sees water, let her perform Ghusl.'" (ES)
English reference (ES): Vol. 1, Book 1, Hadith 198 (ES)
Arabic reference (ES): Book 1, Hadith 199 (ES)