Musannaf Ibn Abi Shayba 33:249

Waki’ narrated to us, from Sufyan, from al-Rabi’ ibn Bazi’, who said: I heard Ibn ‘Umar say: ‘Umar ibn al-Khattab would be brought his bread, his meat, his milk, his oil, his vegetables, and his vinegar. He would eat, then he would suck his fingers and say like this, and he would wipe his hands with his hands and say: "These are the napkins of the family of ‘Umar."