Musnad Ahmad 30:3492

Muhammad ibn Ubayd narrated to us, Ubayd Allah narrated to us, from Khubayb ibn Abd al-Rahman, from Hafs ibn Asim, from Abu Hurayrah, that the Messenger of Allah (peace and blessings of Allah be upon him) forbade two prayers, two modes of dress, and two types of sales. He forbade prayer after the dawn until the sun rises, and prayer after the afternoon (Asr) until the sun sets. He forbade the *ishtimal al-samma’* (wrapping oneself in a garment such that no opening is left for the arms) and the *ihtiba’* (sitting with the knees drawn up to the chest) in a single garment, such that your private parts are exposed to the sky.