Musannaf Ibn Abi Shayba 3:2661

Abu Bakr narrated to us, he said: Muhammad ibn Bakr narrated to us, from Abdullah ibn Ma'dan, he said: I heard Habib, and a man asked him, "What do you say regarding the ghusl (full ablution) for Friday? Is it obligatory?" He said: "I saw Talq, who had come from Makkah to Al-Hajjaj as a captive, and he did not abandon the ghusl on the day of Friday."