He mentioned the hadith and tapped with his hand.
حدثنا أسود حدثنا الحسن بن صالح عن أبي المهلب عن عبيد الله بن زحر
فذكر الحديث ونقر بيده
No references are available.
Its chain of transmission is daif because of Abu Muhallab. But the hadith is sahih based on the previous one.