Sahih Bukhari Volume 3, Book 34, Hadith 2135

حَدَّثَنَا عَلِيٌّ، حَدَّثَنَا سُفْيَانُ، كَانَ عَمْرُو بْنُ دِينَارٍ يُحَدِّثُهُ عَنِ الزُّهْرِيِّ، عَنْ مَالِكِ بْنِ أَوْسٍ، أَنَّهُ قَالَ مَنْ عِنْدَهُ صَرْفٌ فَقَالَ طَلْحَةُ أَنَا حَتَّى يَجِيءَ خَازِنُنَا مِنَ الْغَابَةِ‏.‏ قَالَ سُفْيَانُ هُوَ الَّذِي حَفِظْنَاهُ مِنَ الزُّهْرِيِّ لَيْسَ فِيهِ زِيَادَةٌ‏.‏ فَقَالَ أَخْبَرَنِي مَالِكُ بْنُ أَوْسٍ سَمِعَ عُمَرَ بْنَ الْخَطَّابِ ـ رضى الله عنه ـ يُخْبِرُ عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ الذَّهَبُ بِالذَّهَبِ رِبًا إِلاَّ هَاءَ وَهَاءَ، وَالْبُرُّ بِالْبُرِّ رِبًا إِلاَّ هَاءَ وَهَاءَ، وَالتَّمْرُ بِالتَّمْرِ رِبًا إِلاَّ هَاءَ وَهَاءَ، وَالشَّعِيرُ بِالشَّعِيرِ رِبًا إِلاَّ هَاءَ وَهَاءَ ‏"‏‏.‏

Narrated By Az-Zuhri from Malik bin Aus : That the latter said, "Who has change?" Talha said, "I (will have change) when our store-keeper comes from the forest." Narrated 'Umar bin Al-Khattab: Allah's Apostle said, "The bartering of gold for silver is Riba, (usury), except if it is from hand to hand and equal in amount, and wheat grain for wheat grain is usury except if it is form hand to hand and equal in amount, and dates for dates is usury except if it is from hand to hand and equal in amount, and barley for barley is usury except if it is from hand to hand and equal in amount." (See Riba-Fadl in the glossary).