Musnad Ahmad 937:166

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from 'Ali ibn Zayd ibn Jud'an, from 'Abd Allah ibn al-Samit, from Abu Dharr, who said: "The black dog interrupts the prayer." I think he said: "And the menstruating woman." I said to Abu Dharr: "What is the matter with the black dog?" He said: "I asked the Messenger of Allah, peace and blessings of Allah be upon him, about that, and he said: 'It is a devil.'"