Musannaf Ibn Abi Shaybah

Hazrat Laith says that Hazrat Tawus used to keep his stomach away from his thighs in prostration and his elbows away from his thighs in bowing.

Hazrat Laith says that Hazrat Nafi‘ would keep his elbows away from his thighs during prayer.

Hazrat Laith says that I saw Hazrat Mujahid keeping his elbows away from his thighs during prostration. I have also seen Hazrat Ata doing the same.