It is narrated from Sayyiduna Salamah bin Sakhr (may Allah be pleased with him) that once I made zihar from my wife and had intercourse with her before offering the expiation. Then I asked the Prophet (peace and blessings of Allah be upon him) about this matter, so he ordered me to offer the expiation.
Hadith Referenceمسند احمد / مسند المدنيين رضي الله عنهم اجمعين / 16419
Hadith Gradingحکم دارالسلام:صحيح بطرقه وشاهده، وهذا إسناد ضعيف، إسحاق بن عبدالله متروك، وسليمان بن يسار لم يسمع من سلمة