Musannaf Ibn Abi Shayba 16:834

Abu Bakr narrated to us, he said: Al-Fadl ibn Dukayn narrated to us, from Zuhayr, from Abu Ishaq, from Abu Juhayfah, he said: I saw the Messenger of Allah, may Allah bless him and grant him peace, and this part of him was white, meaning his *‘anfaqah* (the tuft of hair between the lower lip and the chin).