Musnad Ahmad 30:2852

'Abd al-Rahman narrated to us, Sufyan narrated to us, from Abu al-Zinad, from al-A'raj, from Abu Hurayrah, who said: "The Messenger of Allah, peace and blessings of Allah be upon him, forbade two types of sales: al-munabadhah and al-mulamasah. And [he forbade] the wearing of al-samma', and that a man should sit in a single garment [ihtiba'] while there is nothing between him and the ground."