Yahya related to me from Malik that he had heard that a man saidto another, "Buy this camel for me immediately so that I can buy himfrom you on credit." Abdullah ibn Umar was asked about that and hedisapproved of it and forbade it. (ID)
USC-MSA web (English) reference: Book 31, Hadith 73 (ID)
Arabic reference (ID): Book 31, Hadith 1363 (ID)