Musannaf Ibn Abi Shayba 16:1006

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Sufyan, from Wasil, from al-Ma’rur, from Hudhayfah: That ‘Umar saw a black, reddish woman upon her camel-saddle. He said: So he ordered me to cut it. I said: "It is wood." So he left it.