Musnad Abu Ya'la al-Mawsili 140:32

Musa ibn Muhammad ibn Hayyan narrated to us, Kahmas ibn al-Minhal narrated to us, Sa'id ibn Abi 'Aruba narrated to us, from Yazid al-Raqashi, from Anas: That the Messenger of Allah (may Allah bless him and grant him peace) forbade fasting five days of the year: the day of al-Fitr, the day of al-Nahr (Sacrifice), and the days of al-Tashriq.