Musnad Ahmad 31:831

Hashim ibn al-Qasim narrated to us, Shu'bah narrated to us, from Khulayd ibn Ja'far, who said: I heard Abu Nadrah, from Abu Sa'id, who said: Musk was mentioned in the presence of the Prophet, peace and blessings of Allah be upon him, and he said: "Is it not of the best of perfumes?"