Musnad Ahmad 27:1686

Ya'qub narrated to us, my brother's son of Ibn Shihab narrated to me, from his uncle, who said: Salim ibn Abdullah ibn Umar informed me, from Abdullah ibn Umar, who said: I heard the Messenger of Allah, may Allah bless him and grant him peace, reciting the Talbiyah while his hair was matted, saying: "Labbayk Allahumma Labbayk, Labbayk, la sharika laka Labbayk, inna al-hamda wa an-ni'mata laka wa al-mulk, la sharika laka." He said: And I heard Umar ibn al-Khattab reciting the Talbiyah with the Talbiyah of the Messenger of Allah, may Allah bless him and grant him peace, and he would add to it: "Labbayka wa sa'dayk, wa al-khayru fi yadayk, wa ar-raghba'u ilayka wa al-'amal."