Musannaf Ibn Abi Shayba 3:3263

Waki' narrated to us, from al-'Umari, from Nafi', from Ibn 'Umar, that he used to say the takbir from the Dhuhr prayer on the Day of Sacrifice (Yawm al-Nahr) until the Asr prayer of the Day of Departure (Yawm al-Nafr), meaning the first one.