Musnad Ahmad 1153:1917

Ibn Numayr narrated to us, he said: Al-A’mash informed us, from ‘Umarah, from Abu ‘Atiyyah, from ‘Aishah, she said: I truly know how the Messenger of Allah, may Allah bless him and grant him peace, used to recite the Talbiyah. She said: He used to recite the Talbiyah with these words: "Labbayka Allahumma Labbayk, Labbayka la sharika laka Labbayk, inna al-hamda wa an-ni’mata laka" (At Your service, O Allah, at Your service; at Your service, there is no partner for You, at Your service; indeed, all praise and grace belong to You).