It is narrated from Hazrat Sha'bi (may Allah have mercy on him) that if a man accuses his wife of adultery and both do not appear in court, the marriage will remain intact until he performs li'an (mutual cursing).
Hadith Referenceسنن سعید بن منصور / كتاب الطلاق / 2769
Hadith Takhrij«أخرجه سعيد بن منصور فى «سننه» ترقيم الدرالسلفية برقم:، 1591، وابن أبى شيبة فى «مصنفه» برقم: 17665»