It was narrated from Salamah bin Sakhr Al-Bayedi that:
the Prophet (ﷺ) said concerning a man who declared Zihar upon his wife having intercourse with her before compensation: "Let him offer one expiation." (IT)
English reference (IT): Vol. 3, Book 10, Hadith 2464 (IT)
Arabic reference (IT): Book 10, Hadith 2142 (IT)