Sahih Bukhari Volume 2, Book 15, Hadith Number 87

Narated By Muhammad bin Abi Bakr Al-Thaqafi : While we were going from Mina to ‘Arafat, I asked Anas bin Malik, about Talbiya, “How did you use to say Talbiya in the company of the Prophet?” Anas said: “People used to say Talbiya and their saying was not objected to and they used to say Takbir and that was not objected to either.”