Sahih Bukhari
Sales and Trade
Volume: 003 / Book Number: 034 / Hadith Number: 354
Narrated Abu Said:
Allah's Apostle forbade the selling by Munabadha, i.e. to sell one's garment by casting it to the buyer not allowing him to examine or see it. Similarly he forbade the selling by Mulamasa. Mulamasa is to buy a garment, for example, by merely touching it, not looking at it.