Musannaf Ibn Abi Shaybah 6593 — Leaning towards the qiblah and sitting

Mujahid said: After dawn broke, Sayyiduna Ibn Umar (may Allah be pleased with them both) would pray the sunnah rak'ahs of Fajr and then sit with his knees drawn up and wrapped (ihtiba'), and we would sit around him. When he saw one of us dozing, he would nudge him, and he himself would doze while sitting in ihtiba'. Then the prayer would be established, and he would get up and join the congregation.