وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ رَجُلاً، قَالَ لِرَجُلٍ ابْتَعْ لِي هَذَا الْبَعِيرَ بِنَقْدٍ حَتَّى أَبْتَاعَهُ مِنْكَ إِلَى أَجَلٍ فَسُئِلَ عَنْ ذَلِكَ عَبْدُ اللَّهِ بْنُ عُمَرَ فَكَرِهَهُ وَنَهَى عَنْهُ ‏.‏

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. Translation Not Available

Book Ref: Muwatta Imam Malik Book 31 Hadith 1363
Web Ref:  Muwatta Imam Malik Book 31 Hadith 73