Sayyiduna Salim bin Abdullah bin Umar narrates from his father (Sayyiduna Abdullah bin Umar, may Allah be pleased with them both) that a man called Ghaylan bin Salamah al-Thaqafi (may Allah be pleased with him) had ten wives in the Time of Ignorance. When he became Muslim, those women also became Muslim, and the Prophet (peace and blessings be upon him) said: "Choose four of them."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13845