Musnad Ahmad 5:440

Yahya narrated to us, from Ibn ‘Ajlan, Ibrahim ibn ‘Abdullah ibn Hunayn narrated to me, from his father, from Ibn ‘Abbas, from ‘Ali, who said: "The Messenger of Allah (ﷺ) forbade me from a gold ring, and from reciting while I am bowing, and from [wearing] Al-Qassi (silk-blended garments) and Al-Mu’asfar (garments dyed with safflower)."