كتاب البيوع
11  
Business Transactions
(5b)
Chapter: Business Transactions which are Forbidden - Section 2
(5)
باب المنهي عنها من البيوع - الفصل الثاني
Mishkat al-Masabih 2863
Ibn ‘Umar said the Prophet forbade selling a debt to be paid at a future date for another (This is allowing a man who cannot pay a debt when it is due to have an extension of the period in return for an additional sum payable; or when a man agrees to sell an article which someone owes him for money which someone else owes to the buyer. Daraqutni transmitted it.
وَعَنِ ابْنِ عُمَرَ: أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسلم نهى عَن بيع الكالئ بالكالئ. رَوَاهُ الدَّارَقُطْنِيّ
  لم تتمّ دراسته   (الألباني) حكم   :
Reference : Mishkat al-Masabih 2863
In-book reference : Book 11, Hadith 101