Musannaf Ibn Abi Shaybah

Hazrat Humaid says that Hazrat Bakr, when he said the Takbeer-e-Tahreema, would remain silent for a little while. Once, he said the Takbeer and went into Ruku without reciting (Qur'an). Then he raised his head from Ruku and recited, and gestured that you should not go into Ruku. Then he started the recitation from "Alhamdu lillahi Rabbil 'Aalameen."

Hazrat Mujahid says that when you perform ruku and then raise your head, if you wish, you may recite (Qur'an) after raising your head and then perform ruku again, and if you wish, you may perform sajdah as you were doing.