Sahih Muslim Book 7, Hadith Number 2876.

Chapter : Talbiya of the Apostle (may peace be upon him) and his sacrifice.

Anas (Allah be pleased with him) reported: I heard Allah’s Messenger (may peace be upon him) pronouncing Talbiya for both simultaneously, Talbiya for ‘Umra and Hajj. Talbiya for Uwra and Hajj (he performed both Hajj and Umra as a Qarin). In another version words are: I heard Allah’s Messenger (may peace be upon him) pronouncing Talbiya for Umra and Hajj (simultaneously).”